Pura sal literally translates to "pure salt." While salt is common, this phrase is used metaphorically in a very interesting way in the song.
It describes a person's "sweet side" (lado dulce) that ultimately turned out to be "pura sal." This implies that what initially seemed appealing or good about the person was actually bitter, harsh, or ultimately disappointing, like a deceptive sweetness that leaves a bad taste. It's a unique and evocative way to express disillusionment.
Leon Leiden's "Desamor Feliz (Pura Sal)" is all about that moment when you're finally over an ex, even if a tiny part of you still feels something. He's being super direct, saying, "A veces siento que te quiero, oh / Pero sé que no debería, yeh" [Sometimes I feel like I love you, oh / But I know I shouldn't, yeh]. It's a relatable feeling, right? That little lingering attachment, but knowing deep down it's not good for you.
He's basically telling his ex to stop calling him with excuses, making it clear, "Te quiero fuera de mi vida" [I want you out of my life]. The title, "Pura Sal" [Pure Salt], is a clever way to say that what seemed sweet about them turned out to be bitter and fake. He's learned his lesson, realizing, "Por querer salvarte me perdí" [By wanting to save you, I lost myself], and now he's ready to move on because, as he says, "la vida es corta" [life is short]. It's a song about finding your happy ending after a breakup, even if it's a "Feliz, pero con el corazón roto" [Happy, but with a broken heart] kind of happy.