sister fister

The act of fisting your sister. Commonly refered to as incest.

Yo this kid named Francis is a fucking sister fister.

by Quay and Justin October 30, 2003

sister fister

a brother or even a sister that likes to casualy fist their sister up the vagina or even the arse hole. Most of the time resulting in a very sore vagina/anus, and if caught resulting in a sentence of 10 years in jouvey.

(here is a role-play of a sister fister and his sister)
Kirsten after a long sleep
Kirsten: o hi there Aaron i didnt see you over there in that dark corner.
Aaron: You dont need to see me, you just need to feel me
Aaron and Kirsten both grin and Kirsten turns around

by mitch aka titch June 11, 2006

sister fister

Anyone who has shoved their hand into a friend's sister's cunt

1) WOW I PULLED THE SISTER FISTER ON STEPH
2) I pulled the sister fister on blakes sister

by Zane April 05, 2003

sister fister

The act of fisting your sister. Commonly refered to as incest.

Yo this kid named Nicholas O. is a fucking sister fister!!

by Dankolas O. November 19, 2015

Sister Fister

A person who fists peoples sister

amr fisted my dog

by me March 01, 2004

Sister Fister

Nun hand fucker

I fisted the sister during confession

by Mista Fista March 28, 2004

Sister Fister

A bitch you can stick your fist inside of her pussy, no lube necessary. The word sister referring to any random female.

The girl i met last night i was down to fuck, until i realized it was Sister Fister.

by brando239 November 18, 2008