Sanjin Sadou(2002)

Fubuki, a man with silver hair and black eyebrows, is somewhat of an expert at taking care of people's monster problems, for a price of course. Yoru is a strange orphan girl who runs across one of his fights with a demon cat and insists on becoming his student. The two of them make an amazing team, whether they're fighting monsters or (as happens more often than Yoru would like) running from them!