Delirio literally translates to "delirium", but in this song, it takes on a much more romantic meaning. It's used to describe a state of intense ecstasy or madness brought on by overwhelming passion.
Eslabon Armado sings, "Tus besos son mi delirio" (Your kisses are my ecstasy), using this powerful word to express how his lover's kisses make him lose his senses in the best way possible. It's a dramatic and poetic word perfect for expressing intense love.
This song is a straight-up, heartfelt declaration of love. The singer is completely in awe of a woman, telling her, "Me gusta todo de ti / Tus ojos, tu sonrisa me matan a mí" (I like everything about you / Your eyes, your smile kill me). He thinks she's perfect and promises to give her anything she wants, from "La playa, la luna, lo que quieras" (The beach, the moon, whatever you want) to a thousand kisses.
But the real heart of the song is its promise of sincerity. The title itself, "NO VOY A JUGAR" (I'm not going to play games), sets the tone. He assures her that his feelings are real and he's ready for a serious relationship. He even promises, "Ni por coraje te voy a hacer llorar" (Not even out of anger will I make you cry) and that he'll be there for her "en buenas y malas" (in good times and bad). It's a sweet, direct song about being ready to commit and treat someone right.