When two (females) going ass-to-ass and pressing, bumping, rubbing or slamming their asses together.
It's often sexually related, of the who's got the sexiest or biggest butt/ass/booty.
(competitive)
Jake ripped ass last night mid sentence and just carried on talking as if nothing happened. It left me doubting everything. I’m sick of guys asslighting me!
Asslighting (noun): When a large ass first appears smaller than it actually is, causing a person to question their own memory or sanity. See also: Ass illusion, thicc trickery, booty mind games.