Buttered Bun Edit Meaning

1.

Rolling back to the 1970's joy of sex book,a buttered bun is the highest bond between two male friends. To have sex with a woman, cum inside her, and have the other male have sex with her right after him and let his cum get all over his penis.

Oh, here man, I got this woman all buttered up for ya...

2.

The private parts of a woman who has already had sexual intercourse with someone else

I had sex with Mary after the party, but I don't normally want a buttered bun.

See Tom

3.

aka sloppy seconds. Though this one goes back a few hundred more years.