The sentence uses a "mondegreen" or phonetic trick to change the meaning of a single word:

The humor comes from the phonetic overlap between (the girls) and "ananas" (pronounced similarly to "en-nana"). When spoken quickly, the phrase "Brianna... ananas" sounds like a rhythmic rhyme or a nonsensical tongue-twister. 📱 Origin and Context

In French, "une nana" is a common slang term for a woman or a girl, similar to "chick" or "gal" in English.