When having sex with a girl you put your balls into her butt hole. Caution dont not let her tighten her butt muscles hard this can result in a broken ball or two. If your having anal sex try inserting your balls in to her vagina. Variants include single ball penitration, and the more common zero ball penitration.
Obama -"I was having sex with this pornstar in my dreams and she told me to insert my balls in her ass ."
Clinton-" Me and hillary call that double ball penitration"