Átame comes from the verb atar, meaning "to tie" or "to bind." In this song, Mon Laferte uses it in a deeply metaphorical and passionate way.
She sings, "Átame el corazón y déjame las manos libres" (Tie up my heart and leave my hands free). This isn't about physical restraint, but rather a surrender to love, asking her beloved to capture her heart completely while still allowing her the freedom to express her affection physically. It's a unique and intense expression of devotion.
Mon Laferte lays out a simple request and repeats it until it becomes the whole song: "Átame el corazón y déjame las manos libres" ("Tie up my heart and leave my hands free"). She wants to touch — every line after that opener is about her hands, her partner's skin, the closeness of a body pressed against hers.
The tenderness stays physical rather than abstract. She asks to be caressed "con lo suave de tu piel" ("with the softness of your skin") and "con lo dulce de tu voz" ("with the sweetness of your voice"), and calls her partner "mi niña bella" ("my beautiful girl") between confessions that she's gone a little crazy over them. By the closing lines she's not hiding it: "Eres tan bonita, no quisiera perderte jamás" ("You're so beautiful, I'd never want to lose you") — a love song built entirely from wanting someone near.