Seiryuu is a tall, elderly man with long, white hair, a beard and a moustache. He has a patch over his left eye and a scar on his left cheek. He wears traditional clothing and armor, as well as a small hat.
At some point, Seiryuu joined Kou's Empire army and reached the position of Right General.
Seiryuu's first appearance is alongside that of Kouen Ren. He and the Left General, 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 dare he keep Kouen waiting.
By his position and age it's assumed that he has great military skill and experience.
- His first name means Blue Dragon. His last name means Plum.
- "Seiryuu" is the Japanese pronunciation; in Chinese his name would be Qīnglóng.
- He shares the same family name as Seisyun Ri and Seishuu Ri.