Kougyoku Ren (練 紅玉, Ren Kōgyoku) is the Kou Empire's fifth Empress and formerly the eighth Imperial Princess. She was also a general of the Kou Empire's Western Subjugation Army. Kougyoku is the owner of the Djinn Vinea. She is a Dungeon Capturer, capturing one Dungeon, and one of Judar's King Vessels. Due to Sinbad periodically taking control of her mind, she had allied herself with Sindria.
Kougyoku is a small young girl with pink eyes and long, dark pink hair, which is pinned up with her golden Metal Vessel. She usually wears a long, elaborate dress signifying her royalty. She carries herself demurely and often hides her face behind her sleeves when embarrassed.
Kougyoku’s greatest charm is her wealth of facial expressions that convey the various changes in her heart. She tends to act childishly, but there are times when Kougyoku, as the stubborn imperial princess, wears a cold mask in order to overwhelm her opponents at a scenes of diplomacy. Even though she puts up such a willful front, she is actually a very lonely person and wants friends. She doesn't want to follow all of the Kou Empire's orders but is too scared to disobey.
She has always wanted to have friends and close companions, but within her family, she has felt ostracized because of her parentage and has not even had the courage to get to know Hakuei or Hakuryuu, the more approachable of her relatives. Instead, she occupied herself with becoming skilled at kemari by herself, playing make-believe by herself, doing a fashion show by herself, etc.
Kougyoku, who was anxious to have a place for herself due to having a complicated lineage, discovers the meaning to her own existence as a soldier. She fights, willingly risking her life for her important people. She holds a pride greater than anyone else. It is as though it is a way for her to confirm her personal sense of existence.
Kougyoku is the youngest daughter of the First Emperor's younger brother, Koutoku Ren. She has a history like Alibaba Saluja: she wasn't born into royalty like her siblings, because she is the daughter of an unknown, lowly courtesan. She calls herself as a "lowborn".
After the death of the Emperor and his heirs in a fire, Kougyoku's father became the Second Emperor, making her the eight Imperial Princess.
Even in the Imperial Palace, since she had no parents or other relatives, she was forgotten by everyone and felt out of place. However, when she was about nine years old, Koubun Ka was assigned to be her assistant. With his persuasion, he was able to make the princess try harder to do her duties, since from that moment on she was the eighth princess and no longer the youngest daughter of the younger brother of the Emperor.
Kougyoku arrives in Balbadd, at the Fog Troupe base. She saves Judar, after his defeat from Ugo, along with her assistant Koubun Ka. Looking at Ugo, she asks what's up with this monster and if he hasn't bullied their cute Judar too much. Koubun notes that they barely managed to save him. Upon hearing it, Kougyoku adds that he's badly injured and commands him to save Judar, as it won't be a joke if he dies. Then, Kougyoku notices that Ugo still wants to fight. She decides to be his opponent. She uses her Djinn Weapon Equip but after a moment of the battle which she fights with a smile, she becomes more serious and drills a hole through her enemy, thus, defeating him.
She comes back to Koubun and asks how she did and about Judar's condition. As they are about to leave, Aladdin gets angry at her for attacking Ugo and tries to attack her. She asks about Aladdin's identity and comments, "So repugnant...". She wonders about Aladdin's intentions, stating that she merely saved him and his comrades from that monster, but upon learning that Ugo was on Aladdin's side, an enemy whom Judar attacked, she orders Enshin, Entai and Engi to kill the Fog Troupe's members while she will take care of Aladdin.
Then she comments with a smile that everyone seems happy and decides to get serious as well. She gets ready to fight him, but her Djinn Equipping is stopped by Sinbad, much to Kougyoku's astonishment. Sinbad, while holding Kougyoku's hand, notes that she must be the Kou Empire's Princess. After his introduction, Kougyoku stares at him and starts blushing. Embarrassed, she takes her hand away and calls him an insolent man for holding her for so long. Sinbad apologizes but adds that he had to stop her. He says that since they are people of royalty, they should not have a dispute in a place like that and he would like to meet with her somewhere more appropriate. She gets embarrassed and agrees with him. Then, the Princess tells her subordinates that they will return. Before doing so, she explains Sinbad that they aren't returning because of him. While covering her face with her hands, she gets on her Magic Turban and flies away.
Some time after, Kougyoku is in her bedroom at Balbadd's Palace, she asks Koubun Ka about Judar's injuries and he says that will take some time until Judar is fully recovered. Kougyoku says she finds weird to a conventional princess as she be selected for a political marriage, instead of Hakuei Ren, since she is the daughter of the former Emperor. Koubun explains the reasons for such a decision to her, but still, the Princess tells him that she went through a lot just to conquer a Dungeon and she has longed to progress down the path of a warrior. She also wanted to try falling in love for once. Koubun explains that this is Emperor's order and her brother will attend the ceremony as well. Kougyoku exclaims that she's aware of that but admits that she's feeling a little confused. Then, she recalls that according to the tradition, the wedding partners aren't allowed to see each other's face until the wedding ceremony. She thinks that she's starting to have wedding's phobia and wonders what kind of person King Ahbmad Saluja is, hoping that he's someone remarkable.
Kougyoku introduces herself and wants to know who is she going to marry, as she hasn't seen the face of the king yet. When Ahbmad exclaims that it would be him, Kougyoku seems surprised and disgusted, but responds only, "I see...". However, Markkio says that there's a problem, since they don't know who the current king is. She learns that Ahbmad has stepped down from the throne and wonders if that means that it's unnecessary for her to marry him. She quickly scolds herself, reminding herself that she needs to remain calm and complete the mission she was sent to do. She says that she doesn't care whoever it is, as the orders she received was to "marry the King of Balbadd", so she wants the new king to be quickly chosen.
The most obvious answers is the Deputy King, Sahbmad, but he declines and points at Alibaba. Kougyoku asks him if he will become a new king, but he answers he won't, surprising her even more. He says he has no right to be one and explains what he meant. When Kougyoku asks what about tomorrow's signing ceremony, he says he wants to discuss about it. She asks him who he are and after hearing that he's this country third Prince, she wants to know what he has to say. He requests her to destroy the "citizens rights" pact. He says as it was decided by the former King, it has no meaning now. However, Kougyoku says she can't do that and the signing ceremony as well as marriage will happen tomorrow. He says it's impossible, as there won't be new king and today, they will put an end to the monarchy of Balbadd, what shocks her.
After this, Alibaba explains his reasoning. Kougyoku is confused about what to do about the following day's wedding ceremony and wonders what exactly is he saying. Just then, Sinbad appear with his three representatives. When Kougyoku notices him, she blushes. Maintaining serious face, Kougyoku tries to analyze what exactly is happening. Kougyoku interrupts the conversation between Sinbad and Alibaba, saying that all the rights, trade etc., all belong to the Kou Empire. Alibaba replies he understands it well and asks her to act as the rights transfer never happened, what makes her even more shocked than before. He says that as the country of Balbadd they're speaking of no longer exist, so the pacts with Kou have no effect anymore.
Hearing everything, Kougyoku sums up that it's meaningless asks him that if she returned, how would he know that her father won't brush her aside. Alibaba starts to argue with her saying that if she show the kindness now, she will reap the fruits in the future. It's still not enough to change her mind, so Sinbad takes an initiative and says that Balbadd is now under the Seven Seas Alliance. He promises to go to see Kou's Emperor personally and explains all the details to her. She eventually agrees to go along with it. She then takes her leave. After deeply sighing, she is relieved that it got brushed off her hands. In her thoughts, she adds that she'd rather die than marry "that pig".
The Princess returns to the Kou Empire with Koubun Ka and other subordinates on a flying carpet. Koubun asks if it's fine to leave Judar there, but she exclaims that it is, as she left him in Banker's hands. She adds that in any case, they should withdraw for now and should tell His Majesty about the end of monarchy in Balbadd and about the King of Sindria as well. She starts blushing and seems happy. She wonders when Sinbad will make the visit he promised. Then, one of her subordinates points out that the group of people is gathering. Kougyoku, still brightly smiling, says that she knows about it and asks if it isn't outside the Palace, but the man notes that they are heading straight towards the Royal Palace.
As soon as they arrive on Sindria, Kougyoku smiles and greets Sinbad. She thanks him for the other time and adds that it's honor to meet him again. However, when Sinbad, casually, says that there was no single occasion to meet her, she attacks him with her sword and screams that she thought he would apologize and for his country's sake, he would choke back his tears, but in this case, she Djinn Weapon Equips and orders him to fight her to death. She tells him that he deserves death for the brutal act of defiling young maiden's body. Once Ja'far urges her to tell what happened, she blushes and cries. She goes to cry on her court lady's lap, while Koubun decides to tell the story in hear stead.
Koubun explains that when Kougyoku woke up in the morning, when she looked around, she noticed a sleeping, naked Sinbad in her bed. Kougyoku, while still crying, screams that if he denies to fight with her, she will kill herself and if he accepts, she will kill him and then die. Sinbad begins to tell his own drift of events. He says that he drank one of or two sips of alcohol with the Emperor, just for etiquette, and then went to sleep. Kougyoku wants to know why she was in his room the following morning, but Sinbad states that he has no recollection of this. She then asks him why was he naked then and if he naturally removes his clothes while sleeping. Once Sinbad answers "Yes, it happens often!", Kougyoku attacks him again, ordering him to stop fooling around. She asks him if he still intend to feign ignorance and tells him her own version.
She says she wanted to see Sinbad's face once again, she was in the corner, looking at him from behind. She couldn't greet him after all, and disappointed, wanted to return to her room. On her way, she was knocked out and when she woke up, she found out she's in his room. Confused, she jumped out of the room and went to the court lady. Koubun tells him that his only choice is to marry the Princess. Upon not having any support in even his Eight Generals, Sinbad orders Yamraiha to show them what really happened. She is dubious, knowing that her Magic can only show the truth, but Sinbad is sure about it. Kougyoku, though being stopped by Koubun, also agrees. With serious face she states that she wants to know what really happened.
Kougyoku and Sinbad use the drip of their blood and then, Yamraiha uses a special kind of Water Magic, Sharrar Raqesa, to re-create the events of the night. Everyone learns that Kougyoku was knocked out by someone and brought to Sinbad's room where they just slept and nothing happened. However, Koubun demands to not let them deceive her. He orders Sinbad to accept his sins, but the Princess stops him. With tears in her eyes, she says she is sure what they saw is right. She admits that she also felt that something was strange, as neither her hair nor clothes were in disorder, but confused, she panicked. Then she apologizes and starts crying. When the Eight Generals wonder who would do such a thing, her subordinates admit that they helped Koubun Ka to do that. Koubun is attacked by Sindria's soldiers until Hakuryuu interrupts them and apologizes for what the people of his country did. Soon after, Koubun starts crying and Kougyoku consoles Koubun, reassuring him that he's a splendid person.
When Hakuryuu goes to talk to Aladdin, Alibaba and Morgiana, Kougyoku is accompanying him. She says they should get along, despite all the harsh things that happened in Balbadd. Aladdin accepts and she, while recalling what he did to Judar, shakes his hand and says to leave behind what happened and be friends. However, they hold hands really tightly, making each other feel pain. Kougyoku tries blowing on her hand, remarking about the bruise she got. Aladdin, coldly, asks her if she's sure if it wasn't just some powder that got removed, as her hand has a lot of make-up. Kougyoku gets furious and they start "fighting"because he still holds a grudge against her for what happened to Ugo.
When Judar went to Sindria to have a talk with Sinbad, Kougyoku asked him what he meant when he said that the Kou Empire will destroy Sindria. Judar then tells her that she no longer needs to stay in Sindria, even though the mistake she made in Balbadd made her run away from her homeland and stay in Sindria. He asks Kougyoku to return with him. He tells her that he would make her into a general, as she wanted to fight for her country. She takes a look at Sinbad, undecided on which way to get so Judar ask her what's wrong. As she doesn't reply, he proclaims that Sindria is now Kou's enemy and goes away, leaving Kougyoku speechless.
Soon after, Kougyoku asks for an audience with Sinbad. She bows and says that the priest from her country said incredibly rude things and adds that it would be absurd to fight against Sindria, which is bound by a friendship treaty with Kou. The tears well up in her eyes, but Sinbad interrupts her and reassures her that she doesn't have to worry. He takes her hand and says that she can remain in Sindria as long she likes, to what she answers "Y-yes!!".
During the banquet to celebrate the capture of the Dungeon Zagan, Kougyoku is drunk and says she doesn't want to return to home yet. She puts her head on the table and is sure that her father and others would be fine if she didn't come back. She then gets up and very happy, mentions that Sinbad let her stay there forever. Afterwards, Koubun tries to make her get hold of herself, but she continues to lie on the table. When Ja'far invites Koubun for a drink, she wants him to bring her a water. Her wish is fulfilled by Sinbad, whose presence makes Kougyoku happy. He says that he was worried if she was enjoyed the banquet, what she confirms. She admits that she got a little drunk, so Sinbad invites her to walk with him. As he holds her hand, she goes silently, blushing and looking down. She glances at him and discerns his sparkles. She is a little surprised when Sinbad begins to talk. He says that it's mysterious. He mentions that they met in such an unfriendly situation and things will return to being like that time, if it continues on, what makes Kougyoku terrified. He says that right now, they can hold hands like this, what makes the Princess tear up. He says that it would be nice if such happiness could go on forever and leaves. Kougyoku stops him and confesses that she also think that it should last forever. When he turns around and smiles, Kougyoku is even more embarrassed and covers her face.
A few days later, she is in a garden and wonders what Sinbad is doing right now. She is interrupted by Koubun who tells her they've received numerous orders to return to the Kou Empire immediately. She terrifies him by saying that she doesn't want to go home yet, but she quickly laughs it off, telling him to not fall for it. When he leaves, she mutters "Just a little longer...". After this, Alibaba accidentally steps on her flowers. for which he immediately apologizes. Kougyoku, angry that she met him, turns around and says that she heard he collapsed and asks if he's alright now. He replies he is. When Kougyoku thinks that if unlucky, she might have ended up marrying him, he makes a crown of flowers for her and apologizes for stepping on her flowers. She examines it and asks him how did he do it, so he begins to teach her. She comments in admiration that he's very skillful.
Soon after, Kougyoku goes to where Alibaba is to show him the crown of flowers she did after many attempts. He comments that it's made so well, making her very proud. He annoys her by reminding that she was so unskilled at the beginning. As she sees that he was training, Kougyoku invites Alibaba to duel with her, since she was out of shape lately, but he replies that he can't do so, not against a princess. She sulks, saying that she understands their mutual position, but the light spare should be okay. She Djinn Equips Vinea and demands Alibaba to do the same. When he doesn't do anything, she asks him what's wrong and orders to hurry up. She doesn't believe when he tells her that he can't do it, but then, they are interrupted by Sinbad, who comments that her Djinn Equip is splendid. She gets embarrassed and wears off her Equip, saying that she doesn't want to be seen in such an shameful clothing. Sinbad decides to join their Djinn Equip contents. Kougyoku seems a little discouraged, sure that he will be disappointed with her techniques, but he denies, saying that her power is magnificent and asks her to show it to him. Kougyoku happily agrees.
Kougyoku hesitates, saying that she can't point her sword toward Sinbad, but he reassures her that it's alright, telling her that he's fascinates by her qualities as warrior and would be pleased if she showed it to him. They both perform Full Body Djinn Equip and start to fight in the mid-air. Kougyoku does her best but most of her attacks are reflected with Sinbad's Wind Magic. Then, she says that it's incredible, as it's her first time she fights with all her strength. Sinbad agrees and notes that she still hasn't let out her full power, her Extreme Magic. She hesitates, worried about summoning it in such a place, but Sinbad smiles and asks her if she thinks that he won't be able to block it. Kougyoku says, "Well said" and begins her chant. Once she finally executes Vainel Ganezza, it is counterattacked by Sinbad's Foraz Zora. Sinbad then uses Zepar's Sound Magic, which makes her sleep, and finish the fight. Unbeknownst to her, this power also implants a post-hypnotic suggestion in her mind that encourages her to aid Sindria.
When she wakes up, she talks with Alibaba. He tells her what has happened. She admits that she doesn't remember it well and asks about Koubun's and others' state. Alibaba comments that Sinbad's Djinn Equip was amazing, and Kougyoku asks what about hers. He happily answers she was incredible too. She giggles, saying "Hehe, right?". She then says it was a lot of fun. She admits that it was the first time she went wild, with all her strength, without anything holding her back. She says that she was able to do such a thing in this country. She also adds that she feels relieved, although she hesitated at first, she made up her mind: to go back to her own country.
Kougyoku also tells Alibaba that she will talk with her brother, Kouen. He asks Kougyoku what if she had to fight Sinbad, but instead of answering immediately, she admits that he was her first love. She confesses that she loved him ever since the day she met him but adds that she understands that she could never be his love interest, but she loves him nonetheless. She says followed him all the way to Sindria and that she's really an idiot. She starts crying, so Alibaba awkwardly passes her a tissue. She thanks him, but adds that she's alright now and that even though she had a lot of fun in Sindria and could forget about herself by the side the person she loves, it's the end.
Afterwards, Kougyoku asks Alibaba to listen to her story. She says that she wasn't born in the palace and although her father is the Emperor, she's just a lowborn, prostitute's daughter, unlike her siblings. Being in a delicate position, even in the royal palace where she was set outside, she felt out of place. She continues with a statement that Judar and Kouen acknowledged her as a King Vessel and gave her the position of a warrior. She admits that at that time, she thought it was the way she had to live her life. She begins to tremble and tightly holding the blanket, but nevertheless, she says that she was born in order to become a warrior wielding power and fighting for the Kou Empire's sake. She adds that even so, the war between Kou and Sindria is wrong and clearly speaks her mind that she won't fight against Sinbad's country. Later, Alibaba tells her his story. She smiles and says that in this case, he will become her friend. She explains that she never had any friends, since Judar denied it, and they're the same anyway. She asks him if she's wrong, but he doesn't think so and formally says that he is pleased to meet her. She gets angry and hits him in the head. She reprimands him for being so formal with a "friend" and he says he understands. Then, he pulls out his hand with a words of her being his friend, and she, very happy and with tears in her eyes, gladly accepts.
The other day, she leaves Sindria and Alibaba sends her off as if he were close to her.
When Kouen returns to the Kou Empire to attend the Emperor's funeral, Koubun reminds her that she has something to tell her brother. She later goes to see Kouen. During her way, she thinks that it's obvious that he will be the next emperor, and then, the war with Sindria will break out. She dismisses her attendants and is determined to tell him that he's making a mistake. She knows that talking to Judar would be useless, but is sure that in her brother's case, it'll go well. She enters his room and, while hiding, takes a look at him with admiration. However, before she can talk to him, she notices Hakuei there, gets very angry that they seem very close and remains in her hideout. She is relieved a little when Kouen mentions that he has a business with Hakuryuu and is curious what it is about.
Kouen asks Hakuryuu if he wants to become the emperor, much to Kougyoku's surprise. Kougyoku then listens to Kouen's monologue, who starts off by saying that their world needs only one king, what confuses Kougyoku. He mentions that he always wondered what really the "King Vessel" is, about the Torran Language, about wielding a power whose creator they don't know, as they don't know anything about Solomon. He also mentions a world where people talked in different languages and there were many kings, but also existed many conflicts. He asks why there is only one language now but answers to his question by himself. Kougyoku is listening to this conversation more and more surprised and terrified. She is then noticed by Kouen so she comes out from hiding with a big smile. He asks Kougyoku if she heard well about what he said, but she only says that it was all complicated and he is an incredible person after all, but she then wonders why did she said that. She realizes that she missed her chance to talk to him and wonders how can she persuade him after all this talk. Once she acknowledges that she can't do anything for Sindria, she hears a buzzing in her head, what she has been hearing for some time now. She thinks that it seems like someone's voice and wonders what it is. She is then informed by Kouen that Kouha Ren has returned and since it is already late, they will go tomorrow to their father and mother's side.
The next day, Kougyoku and her siblings head to the funeral. Kougyoku and her sisters are shocked to see what has happened to their father and she gets embarrassed when her aunt, Gyokuen Ren, grabs Kouen's arm and asks if he will support her. Terrified, she stays with her sisters, Koubun, Kouha, Koumei Ren and Kouen's Household during the confrontation with the newly appointed Empress.
Kougyoku is in the Kou Empire's Palace when Kouen, who is in Magnostadt, summons her among others through long-range Clairvoyance Magic to come to his place. She answers that she understands and Djinn Equips Vinea.
She appears on the battlefield with Kouen, Koumei, Hakuei and Kouha. She defeats one of the Black Djinn alongside Kouha and joins Alibaba and Aladdin. She is noticed by Alibaba, to whom she brightly smiles. Kouha, astonished, reminds her that she's talking to an enemy's general and asks her why is she so over-familiar with him. She answers that they're good friends. Then, like others, she prepares to the final fight.
She fights against the Black Djinn alongside Kouha. Aladdin then explains that the Medium is a living creature, which also falls under Magoi consumption, and will be able to create around ten thousand more Black Djinn. Kougyoku orders him to stop saying silly things while Kouha comments that it's impossible with their Magoi. At this point, Kougyoku looks already very tired. When Kouen destroys 6 Black Djinn at once, she blushes and happily exclaims "As expected of my brother!!" Afterwards, Kouen digs a hole into a ground. Hakuei explains stimulated the veins of the earth and pulled out a lava flow. Kougyoku asks why would he do that. Aladdin points out that he's doing it to absorb the Magoi from the hot lava to use it for his Astaroth's Metal Vessel.
When Kouen and Alibaba are about to active their Extreme Magics at the same time, Kougyoku asks what's going to happen. After Kouen's attack execution, Kougyoku notes that they're white flames.
The Medium changes it's size and form, what Kougyoku watches worried. Seeing Aladdin speaking with horror that if it touches anything, the victim will lose all the Magoi and will die, she seems surprised. When Kouen gets caught in its hands, worried, she shouts "Brother!!". However, when she notices how badly injured Kouen and Alibaba are after being attacked by the Medium, Kougyoku goes into rage and screams, "What the hell did you do... To my brother and to my friend, you monster!!!". She uses Vainel Arros and tries to pierce the opponent, but is unable to break its defensive wall. Realizing that it won't work, Kougyoku summons multiple spears, Vainel Al-Salos, and declares that she will spear him full of holes. Although some of the spears are stopped by the defensive wall, the rest is able to spear the body of the Medium.
Seeing that it works, Kougyoku once again uses Vainel Al-Salos. Then, Kouen orders Koumei to direct the rest of his siblings. Koumei calls their names, to what Kougyoku, along Kouha and Hakuei, answers "Yes!!!". She follows Hakuei's and Kouha's doing and uses her Extreme Magic, Vainel Ganezza. She makes the tsunami looking like a big spear which makes a huge hole in the Medium. However, when even Kouha's, Hakuei's and Kougyoku's Extreme Magic aren't enough, Kougyoku uses one of her attacks, which, alongside everyone else's attacks, is transported and combined with other's moves through Koumei's Dante Al-Thais. Kougyoku then, completely worn out, watches what happens, but much to her horror, the Medium takes the sea's Rukh and becomes bigger.
Kougyoku is completely exhausted from all the attacks. She however uses water blades to fight once more, saying that she's really unworthy of living, being even reduced to such a state while being near the sea. She realizes that her attacks aren't working against her opponent even without its Defensive Wall. After that, she gets caught by one of the Medium's hands, but Kouen quickly cuts its arm off. Even so, the skin on Kougyoku's legs are torn off, however, she remains conscious. Kouha suffers from it as well, but on the whole body.
When the Medium is about to destroy the world, Kougyoku looks at it angry. However, Sinbad appears and stops it. She then regains her Magoi thanks to Scheherazade, Djinn Equips and alongside others Djinn Equipped people, uses her Extreme Magic to deliver the final blow to the Medium.
She then watches the Medium falling to pieces, hurt and exhausted. Her Djinn Equip wears off and she falls on her knees. Hakuei comes to her side. When the Medium begins to hesitate, Aladdin goes inside it by using Wisdom of Solomon. After his success, she watches the Medium's destruction. When Kouen claims that they came to get Magnostadt and stands against the Seven Seas Alliance. However, when Sinbad looks in her direction, the effect of his previous manipulation takes effect, completely hypnotizing her. She is surprised when Kouen tries to kidnap Aladdin.
Kougyoku is seen in Aladdin's flashback, when she and her family leave Magnostadt riding a carpet.
After Kouen proposes a marriage between Kougyoku and Alibaba, in return offering him full authority over Balbadd, Kougyoku comes to Alibaba, accompanied by her subordinates. When the two of them goes to get a fresh air. Kougyoku notices that Alibaba is deep in his thoughts and tells him that he doesn't seem to well for what he apologizes. She answers that it's fine and says that he is seeing Balbadd after a long time. She confesses that she also was a little afraid when she came there. She says that Balbadd is important place for her as it would have decided her life, given that she married into its royal family. She adds that it's the same even now. With a bright smile, she asks Alibaba if he thinks that things between them improved as well as the relations between Sindria and Kou thanks to fighting a common enemy. She asks whether her brothers realized that Metal Vessels don't exist to make them fight each other. Alibaba tightens his teeth. Kougyoku explains that this is the reason she was called to the meeting as well, as a General of the Kou Empire, much to Alibaba's shock. She adds that for now it's just a decorative title but it's still a great improvement from the times she couldn't even speak. Kougyoku believes it's because they fought the Medium. She explains that right now Kouha and Hakuei are watching over Magnostadt and she could also persuade everyone else, including Judar. She exclaims that she will fight alongside Alibaba and his friends. She says she wants to become his strength, that that's why he can ask her for advice on anything, as she is his friend, and that Alibaba was the first person to accept her feelings outside Kou. She promises to do anything for him. Alibaba looks at her speechless. After a while, he speaks up that it would be easier if she was a despicable person, confusing her.
During their talk, Sinbad takes control of her body. He reveals he is using Kougyoku to spy on the Kou Empire, which enrages Alibaba, who then threatens to fight Sinbad, claiming he'll "never forgive him" for doing this to her. When Sinbad is finished talking, Kougyoku faints into Alibaba's arms. 
Kougyoku encounters Alibaba for the first time after 3 long years. As soon as Alibaba breaks into the royal courtroom and evaded the guards, she ask her men to stand down and let her speak with her old friend privately. Moments later, she listens with a stoic smile to Alibaba who tried to get through her. When Alibaba remarks that he was better in making flower crowns than her, she loses her composure and gets competitive with Alibaba. She laughs a bit and smiles with a bit of blush. She listens to Alibaba's adventures with glee. Then, Alibaba asks her about the stage of the empire and her well-being. Kougyoku notes that Alibaba has seen Rakushou and explains how the old days of playing with Judar as a child were livelier and fun. Because of the restrictions placed by the International Alliance, Kougyoku and her group cannot use Metal Vessels or raise an army to counter the pirates. Furthermore, she attempted many ways to improve the economy such as adopting laws similar to Reim and Parthevia. As soon as Alibaba tells her efforts weren't fruitless, Kougyoku breaks down and cries how Sinbad had used her in the civil war. She is angry and sad that she wasn't able to protect her family, her friends, and the empire. She admits she was angry at Alibaba for not telling her but thank him because she would have faced extreme punishment if Kou Empire had found out. She informs Alibaba that the empire is dissolving due to its ability to pay its loans to the International Alliance after borrowing so much money. When Ka Koubun arrives with a plan, Alibaba assures her and her people that he will save their empire. 
When Alibaba returns to the Kou Empire and tells Kougyoku that he and Morgiana were together, she gives them nothing but her best wishes. 
Kougyoku has shown some skill in swordplay. It's also her special skill.
Vinea is the Djinn of Sorrow and Isolation and its also a water Djinn. She uses her Djinn to summon and control water. When she first summoned it, it appears as a water snake while surrounding her with a "Water Membrane". Kougyoku's Djinn Metal Vessel is a hair pin. The only member of Kougyoku's Household is Koubun Ka. He uses Vinea's water to heal with his Household Vessel.
- Djinn Weapon Equip: Kougyoku is also very proficient in using her Djinn Weapon Equip. She is easily able to call forth her Djinn's power. She usually fights by creating a water tornado around her weapon while spinning. This attack is very powerful, able to blow a hole straight through Ugo's chest and completely defeats him. This is something Judar, a Magi, could not even do although Ugo was greatly weakened from his fight with him.
|“||Spirit of Sorrow and Isolation, in the name of my Magoi, and my will to grant me a greater power, I order you and your members. Come forth, Vinea!!||”|
—Kougyoku, when summoning the powers of Vinea
- Vainel Arros (Water God's Spears): Kougyoku creates a big vortex of water, a spear, around her Metal Vessel and aims an opponent directly.
- Vainel Al-Salos (Water God's Shooting Spears): When she has collected enough spears, she sends them raining down onto her opponents in the same way as Judar's ice arrows.
- Djinn Equip: A fish-like skin covers the surface of her body, with gills and fins. In order to conceal her almost-naked djinn equipped form, Kougyoku wears part of a white robe that serves as a skirt. Her hair turns from pink to blue, and her hair clincher also transforms. Her metal vessel turns into a long blue sword, ornamented with water snake on both sides. She gains two big earrings resembling fins. Kougyoku is very proficient in Djinn Equip. This Djinn allows her to manipulate water currents. Vinea’s speciality fully manifests at sea, where water is bountiful. With this power she is capable of using water currents and membranes to defend external attacks. Her sword is specialised for thrusting attacks, which pierces through all that stand in her way. Its fundamental style is to fight with the blade manufacturing water spirals.
|“||Spirit of Sorrow and Isolation… thou who controls the power to make kings, bring forth the great raging streams that judge the surfaced earth!!||”|
—Her Extreme Magic Chant
- Vainel Ganezza (Water God’s Sea Call): While she is reciting the spell Kougyoku gathers a large amount of water enough water to flood a city is gathered. When she unleashes it, it takes the form of a giant tsunami. She can freely manipulate what shape the tsunami can take as she turned it into a giant spear to pierce the Medium in Magnostadt.
|Quantity of Magoi||
It is shown that the Princess does not have many friends, but is constantly in the company of Koubun Ka and Judar.
Kougyoku appears to have fallen in love with Sinbad at first sight when they met in Balbadd. She becomes very nervous and embarrassed when she's around him. Others have commented that she would do anything he says, a fact that he himself has not seemed to notice. She admits to Alibaba that Sinbad is her first love, but she understands that she could never be his love interest. Kougyoku desperately tries to convey her feelings to him; however, such efforts don’t go well and her first love withers away, short-lived.
In the Kou Empire arc, Kougyoku hates Sinbad since she was forced by him to her betray her family, country and people. Hakuryuu had thought that her relationship with Sinbad didn't look like it changed much, but she claims to never ever ever forgive Sinbad. Though, she is pretending not to hate him at the moment.
When she shows up to the meeting between the Seven Seas Alliance to tell them the Kou Empire was withdraw from them, she tells Sinbad that she wants to forgive him and goes as far as to thank him. She explains that if it weren't for Sinbad's efforts, Kou's civil war wouldn't have ended and comments that he is a great man who has been able to achieve in creating a peaceful world. 
Kouen is Kougyoku's admired older half-brother and an extremely revered figure for her, since he was the one saw through Kougyoku’s abilities and directed her to her own path within the Kou Empire. Also, she seems to be quite possessive upon him, at least respect to women, since she became jealous when Hakuei smiled at him. She cares a lot about his well-being as she was enraged enough to attack the "Medium" immediately after she sees how it severely damaged Kouen. Kougyoku is a little weak when it comes to difficult conversations. Moreover, she shows a facet of herself where she becomes nervous and is unable to tell Kouen the things she intended to tell him.
Although the events in Balbadd, Alibaba became Kougyoku's first friend after they talk about their similar past, both of their mothers being prostitutes. She calls him "Alibaba-chan", showing great affection for him. She cares a very great deal for him, and was enraged enough to attack the "Medium" immediately after she sees how it hurt Alibaba's arm and left it in a terrible condition. She says Alibaba was the first person who accepted her feelings outside of the Kou Empire and that is why she will do anything for him.
Before riding off into war with her siblings to fight Hakuryuu, she is visibly distraught at his death, quietly crying Alibaba's name. The night before the battle at Tenzan, she thinks of him very fondly and prays for him to watch over her.
Judar is the Magi that gave Kougyoku the power to become a soldier. Even within the palace, Judar is a person who Kougyoku can approach for advice and general talk. In the past, Kougyoku mentions how she, Judar, and others used to explore Rakushou as children.  Although Judar has concern towards Kougyoku, he also tends to tease her when he is killing time. He calls her "Old Hag", this makes her get very angry. When Kougyoku tried to be his friend, Judar refused. He tells her that they are not friends. She affectionately calls him "Judar-chan". In Volume 6's Extra, he pats her head and says that "she has a cute side too" which hints they have a friendly relationship.
Before riding off into war with her siblings to fight Hakuryuu, she is visibly distraught, quietly crying Judar's name.
Being Kougyoku’s advisor, Ka Koubun is the attendant who always accompanies and supports her more than anyone. He aims for a top, politically influential position with Kougyoku. He has known Kougyoku for almost ten years.
Aladdin and Kougyoku seem to dislike each other ever since their first encounter. The two have a cat-and-dog-like relationship. For some reason, Aladdin burns with a sense of rivalry with her. Kougyoku dislikes it when Aladdin tells her she has thick makeup. Aladdin does show a degree of concern for her when he asked if she was okay since he thought that she'd be full of hatred toward Sinbad but she said happily that he removed Zepar from her already, and that she was fine. In an extra comic, after they fight, they do show to get along with each other a little better.
During the Final Arc, Kougyoku confides in Aladdin about her misgivings on being the empress. When Aladdin questions why Kougyoku chooses to mention her insecurities to him but not to Alibaba, she replies that she doesn't want to spoil her reputation in front of 'esteemed friends' like Alibaba but feels that Aladdin would be willing to listen to her. This causes Aladdin to ask her if she likes him better than Alibaba to which Kougyoku responds contemptuously with a hair flick and by sticking her tongue out at him, telling him not to flatter himself. It is thus implied that despite Kougyoku's apparent dislike of Aladdin, he is one of the only people she feels comfortable talking to about her real feelings. 
Kougyoku gets jealous easily because she has issues of self-esteem. Hakuei is no exception to her selfish lashing out remarks.
- Her name means Ruby or Crimson Jade.
- Ohtaka made an error on Kougyoku's initial appearance giving her Djinn the same name as one of Sinbad's Djinn. It was fixed in the official volume.
- "Kougyoku" is the Japanese pronunciation; in Chinese her name would be Hóngyù.
- She is the same age as her brother Kouha.
- Her hobby is beauty care and fashion.
- Her weakness is making friends.
- Her special skill is fencing.
- Her favorite food is fruit, but she doesn't like vegetables.
- Her favorite way to spend days off is practicing fencing and bathing.
- She is currently worrying about her lack of friends.
- Kougyoku's type of person is "someone like my big brother, Kouen" and she dislikes oppressive women.
- It was Koubun Ka who gave Kougyoku her hair pin, which is also her metal vessel, when she gained more self-awareness as an imperial princess. Her favorite aspect of the hair pin is the butterfly that is on top of the flower. It is a high class item that has been successfully made to the finest detail.
- She was duped into believing Judar's fake and embarrassing common sense lessons. Actually, Judar fell for it when he was told by Al-Thamen, and so out of spite he told Kougyoku.
- When asked if she has someone on her mind, Kougyoku freaked out and denied it.
- In Volume 27's omake, Kougyoku wishes Kouha were her real brother, stating: "I think we kind of look alike!" Kouha commented: "I think so, too."
- Kougyoku is name after Empress Kougyoku the 35th and 37th monarch of Japan.
- Kougyoku becomes the 5th Empress of the Kou empire when Hakuryuu gives up his throne after he failed to improve the Kou empire's condition.