Perhaps an atheist club should have an evening discussing what is appropriate for them to exclaim during orgasm.
"fate and chemical chance, fate and chemical chance, fate and CHEMICAL CHANCE!!"
Too verbose.
Mere non-verbal but ecstatic sounds are much more appropriate.
Unless, of course, you AREN'T having a nice time.
Best to say or utter nothing, then.
"Politeness is to do or say the nicest things the nicest way".
Let that be your guide,
in flagrante delicto or out of it, if you take my meaning.