One that you Ozoneocean recommended is Hentai Action Theater a wonderful anthology of adult stories, often spoofs of tropes and plots with a sexy bent.

Another great parody send-up of everything is El Cid's epic DeathPorn It's finished now and it's protagonists have gone on to much smaller things but see the comic that swept the Drunkduck awards every year it was running. Dirty, disgusting and hysterical it was like Playboy's Little Annie Fanny on crack.