He has an obsession with Gundam. You need to see a professional, Setsuna. Waaaaiiiitaminute, is that a human-size perfect-grade gundam in your bed in a sexy-like position? Without its external armor? You need help, sir.
Setsuna is likely one of the most human and complex characters I have run across in the anime fandom world. Definitely an interesting guy, even though...I see him more of as a person than an anime guy. ^^;