Surprise! Surprise!

Sh! not so loud: he’ll hear you,
Mary said' from underneath
Roger's thrashing body
and you must use a sheath,
It's one thing now to cuckold him
as he snores away next door,
but when you've finished pumping
I don't want your spore.
There's nothing worse much later
to find your little kickers
are making such a soggy mess
from dripping in my knickers.
What's that you say, I must behave
and stop making it a farce?
My God! A slap across each cheek
you've shoved it up my arse!