Goloso translates to "greedy" or "gluttonous," often specifically referring to someone with a sweet tooth or a strong desire for tasty things. It's a fun and evocative word that isn't as common as basic adjectives.
In "Bésame Morenita," the singer is playfully warned, "no seas goloso" (don't be so greedy/gluttonous) when he's told not to bite too hard. It adds a charming, slightly mischievous tone to the romantic interaction, implying a desire that's almost too eager, like a child wanting all the candy.
Caloncho isn't the first person to sing "Bésame morenita" (kiss me, dark-haired girl). Álvaro Dalmar wrote the song decades ago and Pedro Infante made it a standard long before Caloncho picked up a guitar; what he changes is the groove, folding an old bolero into his own loose reggae shuffle. The compliments pile up fast: her mouth is "Tan jugosa y fresca" (so juicy and fresh) and "Tan coloradita" (so rosy), and a few lines later she's "Como una manzana" (like an apple), "Dulce y madurita" (sweet and ripe). By the time he sings "Y chupa que chupa que es más sabroso" (and suck and suck, it's way tastier), the food and the actual kiss he's asking for have basically merged into one thing.
Then, with no warning, the song drops Spanish entirely for an English verse that reads like a quick, fond sketch of Jamaica: "A face like Bob Marley" and "And a mouth like a motorbike," somewhere where "Well, the bars are always open." It's an odd turn on paper, but it matches how Caloncho actually works, treating Mexican folk and reggae as two ingredients in one pot rather than separate genres. When the chorus swings back to Spanish right after, kissing this girl and picturing a Kingston street corner end up feeling like the same daydream.