Yuuto Kigai

One of the Dragons Of Earth, Yuuto is a bureaucrat working at the Ward Office. He never lets on to any of the happy couples turning in their marriage licenses that he is seeking to destroy humanity, assuming an air of bland cheerfulness which he maintains even in combat

He is in a sexual relationship with Kanoe, and is amused by the knowledge that Satsuki has a crush on him; he sees the latter as a sort of younger sister and protegée, and attempts to educate her about emotions.

In combat Yuuto wields a sai dagger capable of severing human hands with one swipe, and which bears a powerful whiplash attachment that can smash through concrete. He is also a water master capable of summoning floods and hurling water bolts, as well as arranging more benign fountain displays for the amusement of others.

In Tsubasa Reservoir Chronicle:

In Tokyo, he's one of the seven fighters of the City Hall faction. He receives Syaoran's group much more amiably than the rest.