A term girls use when describing another male to their boyfriend that they don't want them to worry about but she is banging his brains out. "Oh don't worry babe he's like my brother." You should definitely worry, he is probably balls deep in her as you read this.
Hanna: Don't worry about Joe, he's like a brother.

By this she means they're getting it on every chance they get.
by Dbauination October 2, 2013
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