When you walk in on your brother (could also be a friend) getting a blow job in your room. It could also apply to other sexual activities.
Ryan: so I walked into my room last night and mary was proving that her milkshake brings all the boys to the yard to my brother.
Callie:Wow! what a slut!!! you should have been like, "now thats a thanks bro if I've ever seen one!"
by cakepan face February 17, 2011
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An act of declining
When the presidence daughter says she want wants some over time with you

-No thanks bro-
by Mangolandzs April 10, 2023
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