Mitarashi Ryuusei♂

The top earner at a club called "Ulysses" in Ginza. He has a short fuse, and is quick with his fists, but he's popular with his clients for his aggressive but professional demeanor (and his ability to hold his breath for over a minute). While he's not the sort of man to hold his tongue for the sake of politeness, he is very careful around people he doesn't think he can trust.

[From official website]