An altertate term for "I agree to that", or "I'll follow you."

It comes from the religious fanatic Jim Jones and his group of followers that drank poisoned Kool-Aid and died after being told that it would take them "heaven".
Ryan - "Eh, I gotta run out to the store, you wanna come?"

Ben - "Yea, I'll drink your Kool-Aid."
by Ben McKnight October 1, 2007
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