Inadvertido means "unnoticed" or "unperceived." It's a more formal and less common word than simply saying something wasn't seen, adding a touch of poetic depth.
In the song, Miguel Bosé sings, "Y el tiempo nos pasa casi inadvertido" (And time passes us almost unnoticed). This line beautifully conveys how deeply engrossed the lovers are in each other, to the point where they lose track of time, making the word particularly evocative in this romantic context.
This duet feels like listening in on a breakup where only one person is actually capable of letting go. The narrator is obsessed with this love. He says “Olvídame tú, que yo no puedo” [You forget me, because I can’t], which is both dramatic and honest. He is stuck, admitting he will “not understand love without you,” and even asks that his body burn if this person is not with him. It is all or nothing for him, and he knows he is on the losing side.
The lyrics move between beautiful memories and the fear of losing them. There are tender images like “Qué bonito cuando el sol derramó sobre nosotros esa luz” [How beautiful when the sun poured that light over us], but then he admits that light went out and got lost. He talks about wanting to “desnudarme como soy” [strip myself as I am] and be like sand that slips through the other’s love, always trying to give more just to keep them. At the same time, there is anxiety and jealousy in “recelar si no me miras con tus ojos, tu boca” [to be suspicious if you don’t look at me with your eyes, your mouth]. The whole song turns on one painful idea: he cannot stop loving, so if this story has to end, the other person will have to be the one to do the forgetting.