Compito means "I compete" or "I contend". It's the first-person singular conjugation of the verb competir.
In the context of this song, the artist sings, "Que yo no compito en nada con él" (That I don't compete in anything with him). This line is particularly striking as it conveys a sense of dignity and moving on, refusing to engage in rivalry over a past love. It's a powerful statement of self-respect and emotional maturity, making it an engaging and memorable word that stands out from typical romantic song vocabulary.
Spanish artist Rels B cuts straight to the awkward truth of running into an ex who barely recognizes who you have become. Right out of the gate, he points out the obvious with "Mírame, sabes quién soy / Claro que he cambiado y tú, también, mi amor" [Look at me, you know who I am / Of course I’ve changed, and so have you, my love]. Success pulled him forward, but it also left an empty space in the crowd. He complains that even though everyone watched him blow up, the one person he actually searched for was missing: "Hay cosas que no pude celebrar, tanta gente y tú no estás" [There are things I couldn't celebrate, so many people and you are not here]. Now, watching her from afar, he wonders who is draining her energy, asking "¿Quién se estará llevando tu luz?" [Who is taking away your light?].
Then he gets petty in the best way possible. Instead of playing the humble ex, he sends a blunt warning to her new partner: "Y dile al nuevo que de mí deje de hablar / Que yo no compito en nada con él" [And tell the new guy to stop talking about me / Because I'm not competing with him in anything]. Calling someone "el nuevo" [the new guy] is wonderfully dismissive in Spanish. He lays down some straightforward advice on how to treat her, saying the guy needs to learn "cuidarte y comportarse bien" [take care of you and behave himself], before admitting both of their hearts still need heavy repair work.