Empleado literally translates to "employee". It's an interesting word choice in a romantic context, as it's not typically used to describe a relationship.
In this song, Nicky Jam uses it metaphorically to describe his subservient role in the relationship, singing, "Pero en los trabajo', baby, soy tu empleado" (But at work, baby, I'm your employee). He implies that he's dedicated to his partner's every whim, working hard to please her, even if she treats him poorly. This unique comparison makes the word memorable and adds a layer of complexity to the song's narrative.
EMPLEADO turns a relationship into a job description, and the joke is right there in the title. The song opens on a guy who knows exactly how bad this looks and says it anyway: "Sale el sol y todavía no he llegao' a casa" [The sun's up and I still haven't gotten home]. He's out all night, dodging her calls, already rehearsing the excuse before he needs it.
The hook cashes in the whole premise: "Pero en los trabajo', baby, soy tu empleado" [But when it comes to work, baby, I'm your employee]. Whatever else is falling apart, he still shows up and takes orders. The rest of the song just keeps listing the damage: "Tengo mis defecto', no soy perfecto, tengo mi pasado" [I have my flaws, I'm not perfect, I have my past]. Nobody's asking for forgiveness here, just credit for admitting it.