Envíciame comes from the verb enviciar, which means 'to addict' or 'to corrupt'. It's a strong and evocative word that you don't often hear in everyday conversation, making it quite memorable.
In this song, the artist uses it in a romantic and passionate way, singing "Envíciame con tus labios" (Addict me with your lips). It expresses an intense desire to be completely consumed by the other person's affection, highlighting a deep and almost overwhelming longing.
"No Te Vayas" is J Alvarez asking someone to stay the night. The hook repeats the title as a plea, "Si tú quieres no te vayas, quédate conmigo ahora" ("If you want, don't leave, stay with me now"), and he keeps circling back to it between verses instead of moving the story forward.
He leans on physical, direct lines to make his case: "Me matan las ganas de tenerte" ("I'm dying to have you") and "Yo soy la cura de tu enfermedad" ("I'm the cure for your disease") cast himself as the remedy she doesn't know she needs. It's a one-mood song built for a single night, not a relationship — the ad-libbed shout-outs to his producers near the end are the only break from the seduction.