A lubricant which one can use to spoil their or their loved ones ass.
Since "Ass Oil" also sounds like "Asshole", it's now possible for members of the gay community to call eachother idiots by saying "Ass Oil!"
Hey man, why are you wearing a dress from last season? You're such an ass oil.
"I'm going to Berlin!"
"Here, take this"
"What is it?"
"It's ass oil, you'll need it."