Hard to say...
I mean... I think Takuma is very perverted and a total sadist - he said it! But not to the extreme...
Kaname has a big chance, because he is extremely sadistic and extremely masochistic at the same time!
Aidou - when it comes to Kaname, a pervert. Otherwise: I'm pretty sure he's the guy acting as if he'sexperienced and all and only has a big mouth in the end, he's probably extremely shy and would run away from everything perverted if it isn't something with Kaname.
Ruka - desperate
Zero - I read somewhere above he's supposed to be a pervert for walking into the bathroom, but that's what tells me he isn't s pervert: he showed no interest in a girl there!
My vote would go to either: Rido, Sara or Kaien. Rido and Sara are obviously perverts because of the
And Kaien... I agree that something is wrong with him because of the daddy-thing, I just can't decide who's worse!