A cereal marathon is when you keep refilling your bowl of cereal while not refilling the milk. Being careful to strain out the milk before each bite so you can keep going as long as you can.
Guy 1: "Dude I've had like 5 bowls of cereal and I've only filled the milk once."

Guy 2: "that's great man...so can you come out to the bar for my birthday party?"
Guy 1: "No sorry I can't. I'm doing a cereal marathon tonight, gotta keep this baby going"
by rterrana691 April 10, 2014
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