when you let someone take a sip of your drink and they drink way too much.
Sister: I just got back from subway

Brother: What did you buy to drink?

Sister: Just an fountain Iced Tea

Brother: May I have a sip? I am rather parched.

Sister: Okay, not too much though.

Brother: *SIIIIIIIIIIIIIIIIIIIIIIIP* *GULP*

Sister: WTF!! I told you not too much

Brother: NINJA SIP!!!!!!!!!!!!!!!!!!
by Fall_backwards December 27, 2011
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