Serenita is the diminutive form of "serena," meaning calm or serene. The diminutive suffix "-ita" adds a touch of endearment or emphasizes a smaller, more delicate quality.
In the song, the artist uses "serenita" to describe a woman who appears outwardly calm and composed, contrasting with the wild lifestyle he leads. It's an interesting word choice because it hints at a deeper meaning, suggesting that her peaceful demeanor is particularly captivating to him amidst his chaotic world.
Calle 24 and Jorsshh bring us a track that's all about a guy who's trying to balance his wild lifestyle with the idea of finding a good girl. He's met someone he calls "mamacita" [hot mama] who's "bien serenita" [very serene] and looks just like her Instagram photos. He even says he's "dejé el desvergue, refuego, las putas" [left the mess, the party, the prostitutes] for her, which is a pretty big claim!
But let's be real, he's still got a lot of his old habits. He admits to smoking weed, doing drugs, and having "varias noches que en mi cama las retaco de locas" [several nights where I cram my bed with crazy girls]. He even brags, "Yo me gané la fama de menearme lo malo y ganar mucha lana" [I earned the fame of moving bad things and making a lot of money]. So while he might be thinking about settling down, he's still very much enjoying the party life, waiting for "la buena" [the good one] to come along. It's a fun look at a guy who's a bit of a contradiction, trying to figure things out.