yamato-no-kami yasusada
A Touken Ranbu character. Official art by Kumita. Voiced by Ichiki Mitsuhiro.
Both he and Kashuu Kiyomitsu are personifications of swords owned by Okita Souji. Unlike Kiyomitsu, who resents Okita for abandoning him, Yasusada is very fond of Okita and hasn't gotten over his former master's death, to the point of dressing and occasionally acting like him.
He has black hair worn in a high ponytail, blue eyes, and a mole under his left eye. His standard outfit is a white scarf, a Shinsengumi haori, black "bridal gauntlet"-type gloves, a dark blue hakama, black tabi and zouri with blue straps.
Normally, he has a carefree personality with his comrades, but is ruthless and sadistic in battles. Of course, artists tend to portray him as someone who's completely obsessed with Okita (to the point of being dismissive with the Saniwa) and who gets violent for no reason. Either that, or he's presented as a foil to Kiyomitsu.
There is also another sword called Yamato-no-Kami Yasusada, which is not currently a character in Touken Ranbu.