A sleep creep is someone who "creeps" out his/her significant other when shacking by doing such things as talking while sleeping, thrashing around, stealing the covers, making strange noises, sweating when its not hot, breathing hard, or opening his/her eyes while asleep.
Aaron is such a sleep creep, he dreamt that he was playing football and actually tackled Vicky in his sleep by rolling her on top of him and staring her in the face.
when someone takes naked pictures of the person they hooked up with that night while they are asleep and then shows all their friends the pictures and gives each other high fives
The Sleep Creep stealthily waits while his unsuspecting drunk partner falls asleep after orgasmic bliss only to be struck upon by the infamous Sleep Creep. The Sleep Creep takes photos of any exposed body part to keep as a trophy and memento to show all of his fellow Sleep Creepers. All the Sleep Creeps then have a round of laughs the next day over a round of drinks and plot for their next night of Sleep Creeping. The photos are not posted on the internet...that is just mean and could get you in trouble! ;-D
The old pervert you meet at the club who drugs you take you home and has sex with your unconcious body. Or could be your uncle who molested you as you slept but you were to afraid to wake up or tell anyone.
If you get drunk with a sleep creep make sure you stay awake or else you might wake up naked with a used condom in your asshole.