Here are some possibilities:
* Typo: It could be a misspelling of "raggin' muffin," which is a slang term for a charming, slightly mischievous person.
* Regional slang: The phrase might be used in a specific region or community with a unique meaning.
* Made-up term: It's possible the phrase was made up for a fictional story, song, or other creative work.
Without more context, it's difficult to determine the exact meaning.
If you could provide more information about where you encountered this phrase, like the context or the speaker's background, it might be easier to decipher its intended meaning.