Yeester
A yeester is when a friend repeatedly punches you in the anus as hard as they can vigorously, similar to sheester in which one repeatedly slaps a males balls with the metal end of a fly swat.
Jordan: "last night I was in the bathroom and Malachi kicked down the door and yeestered my until my butthole turned purple and green."
Mason: " well he sheestered me in my sleep so hard that he scared the crabs back up into my stomach hair."
Mason: " well he sheestered me in my sleep so hard that he scared the crabs back up into my stomach hair."