Cheeky Duck 

The word duck is an abbreviation of the term 'Silent Duck' which refers to the shape made by the hand during fisting, or initiation into fisting. Silent Duck

And so the term cheeky duck refers to slyly slipping a silent duck in during sex, aimed to catch the receiver off guard.

' Hey Freddie guess what?! '

' Woah what happened Sam?! '

' The other night i was having sex and Amy slipped a cheeky duck in! i havent shat right in 4 days! '

Cheeky Duck by s0a0m0 November 25, 2009

Cheesy duck 

The Cheesy Duck is where a man ejaculates inside a woman, and then puts his nose in her vagina much like the bill of a duck.

I'm telling you boy it was filthy, I gave myself a cheesy duck

Cheesy duck by Cosmicdave November 19, 2017