I would say it is a slang for vagina that has reached orgasm.
creampies
creampies
hot dick and anal creampies
Yes, but depending on the flavor of the pie. And depends for how long you bake it too.
Of course they can. He ejaculates inside you. A creampie just means he watches the semen come out.
because their boyfriend wants to see what it looks like when his semen comes out I guess. It does nothing for the woman. It's mostly done in porn.