When a man is about to unexpectedly ejaculate and his partner firmly squeezes his penis to prevent spillage.
Lester: Sorry, babe, I don't wanna nut too early again like last night.
Susan: Don't worry, I'll make sure to cumfirm.
Lester: Sweet!
Susan: Don't worry, I'll make sure to cumfirm.
Lester: Sweet!
by zamzam September 17, 2017
Get the Cumfirmmug.