He is a member of the Japanese Imperial Demon Army and Shinoa Hīragi's squad in the Moon Demon Company. Yoichi has an equilibrium of kindness and altruism, giving him an optimistic and sweet personality. This gives him a strong mental balance against his demon, who takes the form of his sister. He lacked passion to kill vampires and fight and avenge his sister originally, but as he got to know his new "family", he began to see the reason that he was there. Yoichi does dislike conflict amongst friends, but conflict on the battle field doesn't bother him anymore. As time passed, Yoichi is shown to be much more confident with his skills, sniping down three Horsemen at ease by himself. Yoichi is usually the peace maker around Shinoa's Squad. Yuichiro and Kimizuki are usually fighting, and Yoichi often ends up in the middle of it. He has developed a love for his "family" that impacted his personality greatly. He used to get very nervous and stutter a lot, but the closer he got to the Squad, the more confident he got. He doesn't question his self-worth as much as before, and instead focuses more on protecting his new "family".
