Inversor translates to "investor". It's an interesting word choice in a reggaeton song, as it's more commonly associated with finance than with romantic declarations.
In the song, LIT killah uses it to playfully justify spending lavishly on his love interest. When his accountant calls him "crazy" for spending all his money, he confidently replies, "Tranqui, soy el inversor" (Chill, I'm the investor). He's investing in his relationship, showing his dedication and willingness to spend whatever it takes for the person he loves.
LIT killah's "El Inversor" is all about showering someone special with affection and, well, everything! Our guy is completely smitten, ready to spend all his money on this person. He's buying them fancy sneakers, "Air Force One que me llegan de New York" [Air Force One that arrive from New York], and driving them around in his GTI to see graffiti.
He's so head-over-heels that he tells his accountant, who thinks he's crazy for spending so much, "Tranqui, soy el inversor" [Relax, I'm the investor]. It's a funny, confident flex, basically saying he's investing in love! He's ready to fight for her, "Por ella peleo como en Def Jam" [For her I fight like in Def Jam], and gives her all his earnings. If she wants something, all she has to do is "Pídelo, pídelo, pídelo, pídelo, baby" [Ask for it, ask for it, ask for it, ask for it, baby].