Laberinto literally means "labyrinth" or "maze". It's a vivid and evocative word that paints a picture of confusion and being lost.
In this song, the singer uses it metaphorically to describe his emotional state after a breakup, singing "Las tardes son un laberinto" (The afternoons are a labyrinth). This powerful imagery conveys his feeling of being disoriented and trapped in his sorrow, making it a memorable and enticing word to explore.
This song drops you right into the middle of a very bad idea: a late-night phone call to an ex. The singer knows he's breaking a promise, admitting, "Disculpa sé que estoy violando nuestro juramento" (Sorry, I know I'm breaking our oath). He even knows she's with someone new! But he's so desperate he just needs to hear her breathe for a second. It's a dramatic and slightly reckless opening to a song about being completely overwhelmed by heartbreak.
The singer feels like he's literally dying without her, telling her, "Me estoy muriendo, muriendo por verte" (I'm dying, dying to see you). He begs life itself to return his will to live and even the air in his lungs. Without his love, his days are a confusing maze and his nights "me saben a puro dolor" (taste of pure pain). He wishes he could lie and say he's doing great, but as he says, "con un dedo no se tapa el sol" (you can't cover the sun with a finger). You just can't hide a pain this big.