Eriza comes from the verb erizar, which literally means "to make something stand on end," like hair or fur. The common phrase is erizar la piel, which is the perfect Spanish equivalent for "to give someone goosebumps."
In "El Malo," the singer contrasts himself with a more boring, "good guy" rival. He claims the girl will always choose him because he's the one "que te eriza la piel" (who gives you goosebumps), describing a raw, electrifying attraction that the safe choice just can't inspire.
In "El Malo", Dominican bachata group Aventura leans straight into a messy romantic soap opera. The singer admits upfront that he is full of flaws, but he boasts that his ex is still hooked on him instead of her new, well-behaved partner. He even mocks the new guy's lack of charm, singing, "Él no entiende el procedimiento, cuándo y cómo darte un beso" ("He doesn't understand the procedure, when and how to give you a kiss"). To him, good manners cannot compete with pure chemistry.
The lyrics play with fairy-tale tropes in a cheeky way. He calls her "Cinderella" and admits, "aunque yo no sea un príncipe azul" ("even though I'm not Prince Charming"), he is still the one who controls her heart. In Spanish, príncipe azul literally translates to "blue prince," which is the standard Spanish idiom for Prince Charming or the ideal man. He proudly crowns himself the telenovela villain who wins anyway, telling the rival to take notes: "Que anote mis truquitos en papel" ("He should write down my little tricks on paper"). It is cocky and dramatic, built entirely around the idea that being good on paper does not stop someone from craving the bad boy.