When you really fancy someone you say "I want his or her bum". Indicates that you want to hook up with them.

Laura: I really fancy it, he or she is soooooooo sexy!
Kiki:Do you want its bum?
Gemma: I wanted its bum last year, but you can have it, because last year they were a man.
Laura: awww thanks! I want his/her bum!
Kiki: Really? Would you hit that even though you're not sure if they're male or female
Laura: Yeah i don't care they're sexy whatever they are
by kikilaurgem April 26, 2009
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