A sexual act. Performing a Double Penetration with a relative or a close friend while the female is on her period
Dude, me and Jake became Blood Brothers last night. Jess is such a nasty slut...
by Cubsbball25 May 29, 2019
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When two or more guys fuck the same female during that time of the month or

The term for the collection of men who have shared the same bloodly vagina
by Meekis36 November 11, 2020
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A straight man who goes out and/or secretly has sex with men behind their girlfriends/wives back
My lax bro Kevis such an undercover brother, he stops by gay bars every night to hook up with dudes behind his girlfriend s back.
by lil leroy October 24, 2022
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