Nitzan's sister 

A very hot girl, Wich we can't stop speaking about. Sadly, we never saw her in person, but we all know she exists.

What about nitzan's sister?
She's fit!

Nitzan's sister by Wtfactory November 14, 2020

your sister 

One hot piece of ass. Penises can be found in her mouth, pussy, and ass.

Damn, your sister is hot!

your sister by Crackalac July 1, 2003

ur sister 

just like saying ur mom except for a sister as indicated in title

boy 1:u kno who i screwed last night?
boy 2:UR SISTER!!
boy 1:hey, that was mean :(

ur sister by c00kie monsta September 3, 2006

Spunk Brother / Sister 

A half sibling via your father

ie from his 'spunk donation'

usually applying to promiscuous men with more than one family.

I didn't know you had a brother/sister - Oh he's my "Spunk Brother / Sister"

Underlining the fact that the relationship is not a close one.

Spunk Brother / Sister by Big Superfuzz April 2, 2009

National Kiss Your Step Sister Day 

On June 9th it is considered to be National Kiss Your Step Sister Day. On this day it is highly recommended that you make out with your step sister. Any other day it would be considered incest, but on June 9th it is encouraged!

Person 1: Bro on June 9th you gotta make out with your step sister.

Person 2: Why June 9th?
Person 1: Cuz it’s National Kiss Your Step Sister Day, duh.

National Kiss Your Step Sister Day by yomommathic April 18, 2020

ur sister a mister 

even worse than ur granny a tranny. If someone says this, the world literally stops and everyone dies.

Zucc: ur mom gay
Steven: ur daddy lesbian
Zucc: ur granny tranny
Steven: *only slightly offended* ur sister a mister
Zucc *literally fucking dies along with everyone else except for Steven*

ur sister a mister by shsshellysdick May 10, 2018

Thicc Sister 

A Person that has much booty And is willing to join a group of other Thicc beauties. He/she is part of the Thicc sisterhood. They shall not betray the Thicc family.

Joel: “Hey Man Want To Join Ny group Of “Friends”

Aaron: “ Sorry I Can’t. I’m apart of my own family. I’m A Thicc Sister, Boo”

Thicc Sister by Thicccsister June 8, 2018