Definitions by Sexual Conotations

Once upon a mattress 

A term used when someone wants to elude to a sexual encounter between two of more people

Matt: "hey Sam, I heard you met someone new on tinder!"

Sam: "Once upon a mattress . . . "

Matt: "Say no more man, I know how this is gonna end."

Once upon a mattress by Sexual Conotations October 3, 2017

Beef 

The size of a males dick

My girlfriend was soo impressed by my beef last night in bed.

Beef by Sexual Conotations May 12, 2014

Ground Raw Beef 

When a male grinds excessively with a female so long that the skin on the males dick becomes raw from friction

Man last night was amazing but now I've got ground raw beef and it hurts like hell.

Ground Raw Beef by Sexual Conotations May 12, 2014