Hentai where a loser nerd is bullied. He likes reptiles and he prays to a reptile god thing and the snake god literally becomes his penis, uses his now godlike powers to continue to fuck tons of girls, including the main character's sister and mother. For the mother he isn't strong enough so he, while being spanked has to try and cum in her mouth.
Been looking forever, it's kind of jokey, but it's got some good bits.
The picture is NOT from the actual comic, but it looks very similar