While having sex doggy style you grab your partners arm and pull it behind her back and break it. When she turns her head in pain to look at you, you bite her face.
Taken from Robert Deniro's character in the movie "Cape Fear".
Have your girlfriend lie on her back and mount her forehead naked. place your balls on her eyes and your dick on her nose and scream "AH CHA CHA CHA CHAH" or "INKA DINKA DOO".
I gave her a Jimmy Durante.