sai kagerou

First appearance: Battle 286
Type: Sei
Type: Satsujin Ken
Martial Arts: Iaido
Sai Kagerou was a former member of Yami Armed Division. He is a sword master capable of attacking and sheathing his sword without seeming to move, earning him the nickname Otokoeiaigiri. Sai is also double-jointed, allowing him to strike opponents behind him as if they were in front. His Seikuken range is vast, easily encompassing Kenichi who stood several feet away and extending even further due to his towering height and his swords, a Hitokiri Bouchou and Nodachi.
His skills are so advanced that regular swords break under his techniques, unable to endure them. He only feels a connection with Setsunamaru, the Hitogiri Bouchou he received from Shigure's father when Shigure was still a child, a sword able to withstand his powerful techniques. Sai is so dangerous that even Kushinada Mikumo, one of the One Shadow Nine Fists, warned her disciple to study his "handbook." He almost defeated Shigure, showcasing his immense power.
Sai is introduced as a master somewhat careless with his skills, reflexively cutting down an ally while meeting to hunt for Kousaka Shigure. To compensate, he gives instructions on dealing with him, including never pointing a sword at him, never insulting him, and staying three meters away. He remains courteous to both allies and enemies but becomes very excited during fights.
After Shigure takes Setsunamaru from him, Sai loses confidence, reduced to cowering in his shack while birds build a nest in his hair. This extends to his honor, openly begging Shigure to return the sword without regard for his dignity.
Sai cherishes Setsunamaru because any other blade he uses quickly breaks from his power. His love for swords leads to a disinterest in women, whose faces he can't remember (he only recalls Kushinada Mikumo after recognizing her techniques). Though he will use other swords if necessary, he feels no connection with them. When using the Akabanetou, he proclaims momentary love for the new sword and cries for Setsunamaru to forgive his infidelity.