National Fuck Your Freinds Sister Day 

On April 21st of every year National Fuck Your Freinds Sister Day starts on this day you boy or girl will go to one of your friends houses and they are obligated to consent to having you fuck their brians out so in turn on this day woman's right to choose is also temporarly suspended

Josh texts carl: yo its National Fuck Your Freinds Sister Day im coming over to fuck your sister
Carl: Go ahead im about to Fuck Yours
Josh: Narly dude

National Fuck Your Freinds Sister Day by DizzyCannon7211 April 19, 2020

sister fucker

someone from Alabama

get off your your brother you sister fucker

sister fucker by tony's big bologna September 28, 2005

sister fucker

One who makes friends with a guy only to get close to his (usually younger) hot sister.

I thought Kevin was my friend... But it turned out he just wanted my sister. What a shameless sister fucker!

sister fucker by Urban_Fellow June 24, 2006

Sister fucking hot 

A woman so hot that you would fuck her even though she’s your sister. Also the category above a 10 on the attractiveness scale

That girls hotter than a 10. How hot is she?
SISTER FUCKING HOT!!!

Sister fucking hot by Bearickson October 27, 2020

Sister fucker

95% of the people that don't live in a city

Not all truck drivers are sister fuckers but all sister fuckers are truck drivers

Sister fucker by treeman7 June 9, 2018

Sister fucking hot 

A woman so hot you would fuck her even though shes your sister. Also the range above 10 on the 1-10 scale.

Shes hotter than a 10. How hot is she?
SISTER FUCKING HOT!!!

Sister fucking hot by Bearickson October 27, 2020

Sister Fucker

Implies that some one fucks there sister. TO be used in a very derogatory tone. The implication of incest is not acceptable in any culture. It is a very popular saying in India, and will usually result in huge fight when muttered.

Yo Sister Fucker you messed up today's order!
Tobus is such a Sister Fucker!

Sister Fucker by Lanus69 September 30, 2012