On the topic of DxD, well:
Spoiler:
-Yes, Draigr (sp?) does in the end get driven to depression (needing meds too) for his current host's obsession with boobs. Issei eventually gets known as the 'oppai dragon'
The Gremory family somehow turned Issei into a anime franchise and got a entire generation of demon kids loving it...
-He does eventually notice about 90% of the girls want to get in his pants (he's still dense about 1-2 girls though), but then he's afraid of being committed - the fallen angel girlfriend in the 1st Volume subconsciously traumatized him to the point that he's afraid of things being too good to be true, that he'll be abandoned or get killed if he commits himself 100%. He got over this eventually, but he still doesn't get laid either because either a) his harem fighting to be his first, or b) his enemies trying to kill him, or c)
status quo is god no R18 stuff in LNs other circumstances.