Moon Sisters

Girls who have periods at the same time.

Girl 1: Omg i have my period right now
Girl 2: Omg me too! Moon sisters <3

by jtz February 21, 2013

Sister Moon

She is a character from the show Adventure Time and is first introduced in the mini-series "Stakes". The Moon, also called Sister Moon, is one of the 5 vampire's in the Vampire king's court.

To put it simply, she is the best vampire to ever exist in the world of monsters in all universes. Even Lady Dimitrescu's got nothing on her. Maybe. I'm not sure.

Sister moon.
"Die like pigs!"

by SuspiciouslySweetSubstance July 8, 2021

moon sisters

two friends who have fucked in the same room as one another

“omg we became moon sisters last night!”

by katiemeade_10 March 25, 2022

Moon Sisters

When you have sex in a small dorm room at the same time as your roommate

my ex and his best friend came to visit last night. his bsf was totally into my roommate so we became moon sisters over night.

by shawker March 25, 2022