Geek slang for "Bros before Hoes". MMORPG players will often throw this as a trump card when you are trying to spend time with your chick instead of raiding.
Duke: Hey Jim, the raid starts at 8:00ET motherfucker, log your ass in!

Jim: Can't make it tonight, I promised Karen I would watch Sense and Sensibility with her this evening.

Duke: What the fuck man! Brethren before wenches!

Jim: Yeah, you're right. Give me 10 minutes to pick a fight with her and I'll be on.
by Koban December 11, 2009
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