F/K is certainly a very interesting pairing, it's just kinda creepywrong at the same time -- Fuuma killed Kotori. Fuuma removed Subaru's eye. Fuuma did several absolutely traumatizing things to Kamui including attempting to crucify him with glass. For Kamui to then turn around and live with him happily ever after--even changed!Fuuma--that's kinda creepy to me.

Anyway, this is X, so Kamui clearly prefers guys. XD Keiichi it is. (Lately we've been joking around that he should end up with Arashi, because Kamui and Arashi are exactly alike in all the wrong ways, and would bitch at one another merrily for years.)