Jeffy is a puppet character from SuperMarioLogan, the long-running YouTube comedy series built around Mario plush characters and original puppet creations. His high-pitched voice and childlike, mischievous personality made short lines from the show easy to lift for memes, and si papi became one of those repeatable catchphrases shared on soundboards and short-form video. Fans reuse it because it is instantly recognisable to SML viewers while still working as a standalone joke for people who have never seen the show, keeping it in rotation for reaction edits and comedy clips.