In the YouTube series SML (formerly SuperMarioLogan), Jeffy Jeffy is the adoptive son of Rose and Marvin, who he spends his days annoying. He wears a blue helmet and has a shirt with his name written on it by his mom... so he won't forget his name. To fully commit to this costume you'll want to keep a pencil (the rubber variety is recommended for safety) shoved up your nose, and diapers worn outside your pants. The better to keep your diaper clean.

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