closet sister 

two females who are best friends that partake in sexual acts while still maintaining a heterosexual lifestyle

jenna and macy are closet sisters but jenna has a boyfriend

closet sister by swoosh_bear92 June 20, 2011

slay soul sister 

Slay soul sister is a tiktok sound, used in roblox games such as Jiafei’s flop town.

“Slay what you wanna slay, SLAY SOUL SISTER”

slay soul sister by Ch3rry_Bl0ssom May 23, 2022

Kid sister 

A kid sister is a sibling who is a lot younger than you are. Born when you're already grown up.

Example: 10-15+ year age gap

My kid sister is graduating high school today. (Said by a 30 year old)

Kid sister by 331104 July 3, 2018

Older sister 

Person set in charge of you and really is a bitch

That's my older sister. I fucking hate that bitch

Older sister by Nee-chan August 29, 2018

little sister

She has the power to annoy her family, and is very proud about it. She is usually the one breaking the dishes and knocking down cups, and talking back to her parents. Although she may be clumsy, she is very intelligent. They usually have the stereotype to be the troublemaker and the least responsible in the family.

My little sister broke my nails!
My little sister stole my attention.

little sister by 20yo202002 December 26, 2014

Big sister 

Sometimes a pain in the ass, sometimes someone you never want to talk to again, but other times can make all the bad things that happen go away when its all said and done.

Big sis: Why are you so sad??
Lil sis: Big sister the kids at school are mean
Big sis: aww well I love you!

Big sister by yhctirt May 31, 2009

Bitchy Little Sister 

The most evil bitchy thing in the world. All of satan and hell comes from inside of her. When you try to do nice things for her, she botches and complains and tries to get you in trouble. She is also extremely annoying. Biggest Blackmailer

Little Sister: Hey Michael can you fly my helicopter with me?
Big Brother: Bailey im in the middle of something.

Little Sister: If you don't I will tell mom that you snuck out last night.

Big Brother: UGH fine lets go now.

(later while flying helicopter)
Little Sister: It wont fly fix it michael NOW.

Big Brother: I cant!!!
Little Sister: (on phone with dad) Dad michael hit me!!!!
Dad: Mike youre grounded
Big Brother: WHAT????
Little Sister: HA! Now fix it or ill get you more in trouble. You ruined it didnt you. You were jealous i got one so u broke my helicopter. Im telling mom.
Big Brother: Wow bailey your such a bitchy little sister

Bitchy Little Sister by whitekracker August 18, 2011