Boyan is a tall man. Initially, he wears a typical Kouga's outfit, consisting of white robe with a dark belt around his waist. Later, he wears the Kou Empire's armor.
Boyan has a rather cheerful personality, as he's usually seen with a smile.
Nothing is known about Boyan's past.
Afterwards, Boyan comes back home from hunting. When Toya and Aladdin come to Dorji, Boyan and Bator smile and address to Toya. Boyan tells her that Dorji got a deer for her, while Bator adds to tell him that he's the best. In the evening, during the fest, Boyan fools around with Toya, Dorji and Bator. Later, Boyan is seen during the negotiations with Hakuei Ren, but he is only watching silently. However, when Ryosai hits Toya, he seems very horrified.
When women from the village are kidnapped, he goes to save them. After the rescue of women, he comes back with a big smile. He watches Baba when she starts telling Kouga's people that the most important things are their lives and looks very happy after she ends her monologue. During evening's banquet, he laughs at Dorji after he blushes because of Toya's comment.
Some time later, Boyan notices Baba's disappearance and asks Dorji about her whereabouts. After Baba gets shot and the Clan is discussing whether they'll submit to Kou or wage a war against them, Boyan is terrified while watching a progress of the conversation. He is also fighting against Hakuei and Seisyun Ri and is surprised by Baba's sudden appearance, remarking about her wound.
After Baba's death and Ryosai's defeat, Aladdin is leaving the Kouga Village. Boyan is seen in the group of people seeing him off. He smiles seeing Aladdin blushing that a man of caravan called him one of Kouga's siblings. When Aladdin asks if he really can have Baba's staff and gets a positive response, Boyan offers him taking a weapon instead, as traveling alone can be dangerous. However, the weapon he wants to give him is the same Goltas used, so Aladdin tell the gathered Goltas' story. He bids him a farewell with a big smile.
Boyan is rushing to the Kou Empire on a horse along Hakuei Ren, who will attend the Emperor's funeral, Seisyun Ri and the other members of the Kouga Clan. There, he is introduced to the Prince Koumei Ren by Hakuei as a member of her Household.