Bemba is a fantastic slang word from Caribbean Spanish for "lips" or "mouth", often referring to thick lips.
In the song, Beéle cleverly plays on the old saying "the walls have ears" (las paredes tienen oídos). He adds, "También tienen bemba" (They also have mouths), painting a vivid picture of how gossip spreads as if the walls themselves are talking. It's a memorable word that perfectly sets the song's theme of rumor and suspicion.
This song by Colombian artist Beéle is all about that horrible feeling when you think your partner is cheating on you. He's hearing rumors from everyone, saying things like, "Muchos me dicen que ya hay alguien más" (Many people tell me there's already someone else). The walls are talking, and he's getting paranoid, noticing she's acting "distante, un poco arrogante" (distant, a little arrogant).
He spends the whole song imagining what would happen if he actually confirmed his fears. The title itself, "Si Te Pillara" (If I Were to Catch You), is a threat and a fear all at once. He admits he'd fall apart, singing that his eyes would get watery and "Si tus labios pillo con otros, lloro" (If I catch your lips with others, I'll cry). It's a classic reggaeton mix of heartbreak and a little bit of drama, all about the agony of suspicion before you know the truth.