jack in the slat
when you totally bone your girlfriend and then blast your load on her privates. it's like you're saying ‘i'm not done yet’ and you're giving her a free slat face.
my friend jacked his girlfriend in the slat and now she won't stop laughing at him.
i tried to jack my girlfriend in the slat but she ran away and i got stuck in the hallway.
he said he’d jack her in the slat if she promised to never leave him.