slack flaps 

term used to describe a woman who has loose morals in the sex department, has put out so much that theres no tread left on the tyres.

i was doin this chick last night, she had slack flaps.
her flaps were so slack it was like feeding a kitkat to a whale.

slack flaps by paddy donnelly September 10, 2006

Sack Flaps 

Sack Flaps are a rare genital disease that gives the unlucky victim an extra, saggier pair of nuts. This extra pair usually hangs lower than the typical pair.

Hey bro, do you have sack flaps!?? I could see them through your thin leggings.

Sack Flaps by tambah May 1, 2024

a raging sack of cunt flaps 

Someone who is even more heinous than a cunt, because “cunts are still useful”.

What a raging sack
Of cunt flaps!!!

Or, Ed is a raging sack of cunt flaps.

a raging sack of cunt flaps by Smartmouth78 August 12, 2023

Flap Stack 

The act of two guys double penetrating a girl by having the girl sitting face forward on one guy (reverse cow girl anal style) and being vaginally penetrated by the other guy facing her.

Michael and Cory totally flap stacked that girl from their acting class.

Flap Stack by giraffeafrass October 11, 2010

Flap Sack 

Loose skin on your balls do to tiny nuts

Man mark temple has some flap sack showing through his shorts ..!

Flap Sack by Flap Sack April 22, 2021