"Mami" is a flashy, flirty corrido-style pitch to a woman the singer is crazy about. He opens soft, "Mami, solo déjame cuidarte un poquito" (Babe, just let me take care of you a little), and promises "me porto bonito" (I'll behave nicely). Mami here is not mom: it is everyday Latin slang for babe or baby.
Then the money comes out. He wants to treat her "fancy" (an English word dropped straight into the Spanish), says he would buy her the whole world and hand her a Ferrari if she wants it. It gets blunt fast: one chorus line is openly about her body, so this one is not for the classroom. The sweeter touches are the little words: "corazoncito" (little heart) and "cora", a clipped slang form of corazón, plus a tattoo of her "ojitos tan bellos" (such beautiful eyes). The last line is a shout-out, "así suena la Gemeliza" (this is how the Gemeliza sounds), the twins' name for their own crew and sound.