When you and bro have sex with a set of sisters.
Mark- Mikey, you fucked Cheri, right

Alex- {Hell} yeah I did.
Mark- Good, I fucked her sister. Put it here my sister slammer.
by H7476 October 28, 2017
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The act of screwing your sister.
Not a name to be proud of.
Nasty, gross and wrong.
Usually due to country lifestyle.

see incest, inbred, redneck.
Random Guy: Dude, did you hear? Last night john screwed his sister.

Random Guy2: Ew... Bekka? He's a fuckin' sister slammer
by bradski September 27, 2007
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