When a girl is dying to give you some head but you just aren't in the mood for it -- you ask her for a braincheck.
Tim: Vicky really wanted to give me a blow job last night...
Ryan: So did she?
Tim: Nah, I had just hooked up with her room mate, so I asked her for a braincheck.
Ryan: So did she?
Tim: Nah, I had just hooked up with her room mate, so I asked her for a braincheck.
by J Ganthier October 13, 2008
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