Enloquecer means "to go crazy" or "to drive mad." It's a dramatic and expressive verb that conveys a strong sense of losing control.
In the song, the singer uses it to describe the intense emotional state of missing someone so much that they feel like they are losing their mind: "Cuando no duermo siento enloquecer" (When I don't sleep, I feel like I'm going crazy). This word captures the passionate and almost desperate tone of the lyrics, making it very memorable.
"Al Pasar" is a simple, direct plea from Kabah's early catalogue. Someone spots a person walking by and decides, right there, to go after them. The whole song sits inside that one moment: "Sigo tus pasos, te quiero alcanzar" (I follow your steps, I want to catch up to you), before he's even said a word to her.
What makes it work is how unguarded the asking is. He doesn't dress it up. "No tengas miedo, déjate querer" (Don't be afraid, let yourself be loved) is about as plain as a pickup line gets, and the bridge repeats the question two different ways: "¿Cómo decirte que me muero por ti?" (How do I tell you I'm dying for you?) and "¿Cómo pedir que estés aquí?" (How do I ask you to be here?), like he's rehearsing it before he actually says it out loud. By the time he admits "Pierdo el control sino te vuelvo a ver" (I lose control if I don't see you again), the crush has fully taken over.