Delirio translates to 'delirium' or 'madness'. It's a powerful word that suggests a state of wild excitement or ecstasy, almost like being in a dream.
In this song, Sie7e sings about a "delirio de cabeza" (a delirium of the head) to describe a love and happiness so intense that it feels unreal and overwhelming. It’s a beautiful, poetic way to express a feeling that goes beyond simple joy.
This song is all about giving someone the most important thing you have, even when you have nothing at all. Sie7e starts by saying he has a gift for someone: "Te regalo una promesa" (I give you a promise). But then he admits he's struggling to explain something important: "No sé cómo decirte, mi bien / Que no tengo nada" (I don't know how to tell you, my dear / That I have nothing). He has empty hands, but he's full of a joy that makes material things totally unnecessary.
His real gift isn't something you can hold. It's a promise of a happy future, a life that feels brand new, and his complete, honest self, or as he puts it, his "alma desnuda" (naked soul). He knows this promise of pure happiness might sound too good to be true, even admitting it "parece una mentira" (seems like a lie). But for him, this feeling is a "delirio de cabeza / Que no tiene dudas" (a delirium of the head / that has no doubts). It's a beautiful way of saying that love and happiness are the only things worth giving.