It's an abbreviation for "Gotta Peter." It mean you have to leave or you're making up an excuse for not wanting to go somewhere.
Girl: U wanna come over?
Boy: I would, but you know...
Girl: Know what?
Boy: I gotta Peter
Girl: What does that mean?
Boy: It means I can't.
Girl: No it doesn't.
Boy: How do you know?
Girl: I just look it up in Urban Dictionary it mean you don't want to.
Girl: Hello?
Girl: HELLO?!
Mom: We're going to the grocery store.
Child: Gotta Peter
Boy: I would, but you know...
Girl: Know what?
Boy: I gotta Peter
Girl: What does that mean?
Boy: It means I can't.
Girl: No it doesn't.
Boy: How do you know?
Girl: I just look it up in Urban Dictionary it mean you don't want to.
Girl: Hello?
Girl: HELLO?!
Mom: We're going to the grocery store.
Child: Gotta Peter
by Bruzzese August 12, 2016
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