Libreto literally translates to "script", like the one used for a play or movie. It's a fantastic word that isn't commonly found in song lyrics.
In "¡Corre!", Ivan Cornejo uses it metaphorically to describe a relationship that has become painfully predictable. He sings, "Libreto de siempre, tan predecible" (The same old script, so predictable), suggesting that their conversations and arguments are like a scene they've acted out many times before. This creative use paints a vivid picture of a love that has lost its spontaneity.
Ivan Cornejo takes on a classic breakup anthem and brings his signature moody Regional Mexican style to it, singing to an ex who has mentally checked out. From the very first lines, everything feels cold: Me miras diferente ("You look at me differently") and Me abrazas y no siento tu calor ("You hug me and I don't feel your warmth"). The narrator knows the routine too well. Whenever he tries to speak, the partner cuts him off and claims to always be right, turning their relationship into a tired movie rerun (Libreto de siempre, tan predecible ["The usual script, so predictable"]).
Instead of begging for them to stay, he tells them to hurry up and leave: Así que corre, corre, corre, corazón ("So run, run, run, sweetheart"). He points out with some sharp sarcasm that between the two of them, the ex was always the fastest runner anyway. There are no tears left to give, and he makes it clear he will not be chasing after them (no iré detrás ["I won't go after you"]). By the end, after going through too many fake goodbyes, he decides that even writing one more line for this person is a waste of time (Dedicarte un verso más está de más ["Dedicating one more verse to you is too much"]).