I have done this with a married couple and it was totally amazing for all 3 of us.
His wife felt a very large "lump in her cunt" as she put it.
He and I felt turned on by feeling another cock on the soft underside of our dicks with pussy juice making everything all slippery.
She came so hard, she nearly broke my dick.
Then she took both our cocks in her mouth and "cleaned" us up.
I can still see the smile on that woman's face in my mind's eye.
Helping people have sex like that is WONDERFUL.
We shared it and we loved it.
Y'all try this!!