I'm pretty sure they do it when he's in his demon form in the sequel...
isn't he always a demon tho just because he looks like a kid doesn't mean his not old if that was the cause I'm screwed ┑(￣Д ￣)┍
Yeah he's still a demon XD I meant when he was in his full form but I didn't really say that properly in my comment :P
In continuation manga...have no clue what is the name....They have with Endo's demon side ^*^
XD Kinda wish that they fucked while Endo was a demon but I still love this so much!