Shaniqua: "So basically yeah, you know Tyrone? Yeah he threw me on the bed when we was gettin' freaky yeah and slid in all Snake like a Back-Door Bandit fam and he was sweatin' and wheezin' all over me yeah you get me?"
A late night hook-up that you met on tinder (or any "dating" app) and you don't want your roommates to see them because they are well below your usual standards. So you sneak them in through the back door.