One who is keen on the idea of anal penetration but is not quite ready to allow insertion of implements, whether human appendages or sexual toys.
Him: Sounds like you're desperate for a bumming.
Her: I'll be honest with you, I AM curious but not curious enough.
Him: Sounds like you are bum-curious to me.
Her: Well heres the deal, If yours goes anywhere near mine, My finger goes up yours
Him: Unless you are drunk, you mean?
Her: My bum is fair game if I'm drunk.