Sinvergüenza literally translates to "without shame" (sin + vergüenza). It's a powerful word used to describe a scoundrel, a rascal, or someone who acts without remorse or regard for others.
In this fiery anthem, Christina Aguilera calls her ex a bandido y sinvergüenza (a bandit and a scoundrel) for his womanizing ways. It's a classic, dramatic insult that perfectly captures the song's defiant and empowering tone, making it a fantastic word to add to your vocabulary.
Christina Aguilera steps up to answer the famous traditional Mexican ranchera theme of "the king" who does whatever he wants. She kicks things off by dismissing common break-up remedies: people claim time heals everything (Dicen por ahí que el tiempo lo cura todo) or that booze makes you forget, but she doubts her ex can ever forget her kisses, which she proudly states "are worth more than gold" (Valen más que el oro). She calls him out directly as a shameless player (descarado, un bandido y sinvergüenza) who has women raining down on him without carrying an umbrella (caminas sin paraguas), not caring who he hurts along the way.
The real power of the track comes from her turning heartbreak into a firm boundary. She admits that she sobbed the day he walked out (Y lloré, y lloré, y lloré), but that breakdown fueled an oath: no man will ever make her sad again (ningún hombre volverá a ponerme triste). He might still fancy himself the king, but she leaves him with the ultimate punchline: he is stuck ruling an empty court because he lost his queen (te quedaste sin la reina), and without her, he is nobody at all (no eres nadie sin la reina).