Pendejo is a very common and versatile slang term in Spanish, often used to mean 'idiot' or 'asshole', but it can also refer to a 'coward' or a 'fool'. It's a strong, informal insult.
In this song, the artist uses it directly to call out an ex-partner, singing, "Porque tú ere un pendejo y yo sé que nunca vas a cambiar" (Because you're an idiot and I know you'll never change). This word choice adds a raw, emotional, and confrontational tone to the lyrics, making it memorable and impactful.
"No Te Deseo El Mal" spends three and a half minutes insisting it holds no grudge while listing every bad thing it hopes happens to an ex. The hook is the whole joke: "No te deseo el mal" ["I don't wish you bad"], followed immediately by hoping a cop finds "un kilo encima" ["a kilo on him"] during a routine stop, or that his next flight kicks him off "por no tener mascarilla" ["for not wearing a mask"]. Eladio Carrión and Karol G trade verses building the same bit back and forth: never a real threat, always a specific inconvenience.
The second verse doubles down instead of cooling off. She hopes he "te quedes sin gasolina de camino a tu boda" ["run out of gas on the way to your wedding"], hopes "Y también te la quite Neymar" ["Neymar steals her from you too"], and hopes the cops search his car and find "cocaína con baking soda" ["cocaine cut with baking soda"]. By the time she admits "el mal no te quisiera desear" ["I wouldn't want to wish you harm"], the song has already spent two verses doing exactly that.