Seiryuu is a tall man with long white hair and a long white beard. He wears a small hat and has a patch on his left eye. He also has a scar on his left cheek. He wears traditional clothing and armor.
At some point, Seiryuu joined Kou's Empire army and reached the Right General position.
Seiryuu's first appearance is produced along with Kouen Ren's first appearance. He and the Left General of the Kou Empire, Kokuhyou Shuu, are standing at the army's base in Balbadd, in front of the throne where Kouen is sitting, waiting for Judar's return. When Judar comes in, along with Koumei Ren and Kouha Ren, Seiryuu questions Judar, asking how he dare makes Kouen wait.
For his position it's assumed that he has strong military skills and experience.
- His name means Blue Dragon in Japanese. His last name means Plum.