Mareo means 'dizzy' or 'dizziness'. It's an interesting word because it can describe a physical sensation, but in this song, it's used in a more provocative and metaphorical way.
The lyrics say, "Yo doy mil vueltas arriba de él hasta que lo mareo" (I go around on top of him a thousand times until I make him dizzy). Here, 'mareo' implies not just physical dizziness, but also overwhelming someone with passion and intensity, making them lose their bearings and focus entirely on the singer.
Yailin la Mas Viral's "Todos Mienten" is a super direct song where she's basically telling another woman to give up on a guy because he's with her! She's not holding back, calling the other woman a "Maldita perra" [damn dog] and saying things like "No tiene voltio pa' quitarme un hombre, tú eres un cuero" [You don't have the power to take a man from me, you're a slut].
It's all about Yailin claiming her territory and letting the other woman know that the guy is lying to her. She even taunts her with lines like "Y llámame, pa' que lo veas roncando Encima de mí, como un niño babeando" [And call me, so you can see him snoring on top of me, like a drooling child]. The repeated phrase "Olvídate-date de él" [Forget about him] really drives home her message that this guy is hers and the other woman should just move on. It's a bold and confrontational track!