Chijoku no Seifuku.

Is your neighbor rude to you? Fuck his wife. That's the moral of this story. Well, it would be if it stopped there. But our protagonist also decides to place spy cameras in another chick's apartment to blackmail and fuck her for no reason. Well, for no reason besides getting his dick wet that is. He even blackmails and enjoys a nurse, building up his harem, one slut at a time. (These OVAs are based on the erotic game by Bishop.)