Dangerous mixture of Blacking Out and Jacking Off
After a long night of binge drinking and chasing loose women, you somehow end up alone. You then proceed to pull out your erected penis, and during masterbation, you pass out. The next morning you wake up with your pants around your ankles and no recollection of what happened.
Dude, I think my roommate blacked off again last night! I can't find my lotion and he is passed out on the coffee table buck naked.