Age: 16 (past), 28 (future), 18 (final arc)

Birthdate: October 18, 1989

Blood type: B

Height: 177 cm (5'10")

Weight: 64 kg

Hair color: sunflower blond

Eye color: blue

Seishu Inui is the former 10th generation Black Dragon commander.

Inupi is of average height and has a slim build. He is often seen dressed in uniform with high heels, making him appear taller. His skin is pale and his left eye is tainted with a deep burn scar from a fire when he was young. His middle-parted sunflower blonde hair contrasts his dark emerald eyes and neutral expression.

Inui is usually a stoic and quiet individual. However, he isn't afraid to voice his thoughts and opinions even if it hurts him in the end. He is very committed to the Black Dragon and loyal to Kokonoi, whom he considers his best friend. When he finds people he trusts, he devotes himself to them. He is brave but willing to show his vulnerable side and open up to those he trusts.