Despierto literally translates to "awake". It's a common word, but its usage in this song is what makes it special and poetic.
In the lyrics, J Balvin sings, "Pero te soñé despierto" (But I dreamed of you while awake). This beautiful contradiction is a Spanish way of saying you're daydreaming or thinking about someone so intensely that it feels like a vivid dream. It perfectly captures the song's theme of being haunted by the memory of a past love.
Ever thought you were completely over someone, only to have a single song throw you right back into the memories? That’s exactly what happens in this track. J Balvin and Bad Bunny trade verses about trying to forget a past love. Bad Bunny admits he thought he'd moved on, but he was just fooling himself: "Pensaba que te había olvidado / Pero pusieron la canción" (I thought I had forgotten you / But they played the song).
He thought sleeping with other people would work, but it didn't. He even says he "nunca te superé" (never got over you). The song triggers a flood of very specific, very steamy memories for both of them, from being drunk together to intimate moments in a car, on a beach, and even at her parents' house. J Balvin says he was happy she was with someone new and he hadn't even been missing her, but the music changed everything. It’s a perfect song about how powerfully music and memory are linked, for better or for worse.