Eruru Kariya

Eruru Kariya (刈谷) is another protagonist in this story, and the youngest of them all. She also looks younger than she really is, being Hisui's age and yet looking like a middle-school child. Unlike the other heroes however, she is not a school student. She has actually graduated from college. In fact, she has a job with the Metropolitan Police Department, working in the supernatural investigations section. It is first assumed that she is the head of the section but it is actually Rangetsu Oogami who commands it. Eruru is like an interim leader, taking care of one's place when they are not around. Only Hisui and Rushella know this at first, but Eruru is actually a dhampir, half-human, half-vampire. She dislikes her father, and because of this, she originally shows a lot of disrespect to vampires.

Eruru has quite a troublesome personality around people. She is cold, and does not sugar coat whatever is in her mind. If she intends to say something mean, she says it directly. She does not care about how this affects anyone. But when she acts nice, she seems adorable. She also has a bad habit of calling people names at any time of the day, and does so either because she feels like it or simply to hurt one's feelings. She also ignores others whenever they try disturbing her. It is also hard to make her smile, and only Hisui has done this, but it happens very rarely.

Eruru has no love interests, but she slowly comes to understand how she feels about Hisui, though it is likely she is not in love with him. Because of having a hard exterior, she hardly understands her own feelings at all.

She first appears in Volume 1