I remember an H-game I played recently called Dark Blue where there was a route that the protagonist would tie up one of the female character after she rejects him, hook up jumper cables to her nipples and send electric shocks through them. After some time the pain from the shocks cause her to defecate, and the protagonist takes the defecation and feeds it to her, tapes her mouth shut, then takes the tape off a little bit later to which the girl throws it all up, afterward he precedes to have sex with her, cut her and another girl in half, and sew the two halves together.