Patrocinar literally translates to 'to sponsor' or 'to finance', a formal term you would typically expect to hear in sports, brands, or business.
In this song, Xavi uses it playfully when he tells his crush, "te voy a patrocinar" (I am going to sponsor you). It is a humorous and modern way of saying he wants to completely fund her luxurious lifestyle, treating her to designer bags and lavish VIP vacations in Cancun and Dubai.
This song is a wild declaration of love and luxury! Xavi is completely obsessed with a girl and is basically promising her the entire world. He's not just offering a nice date; he's talking about flying private, never tourist class: "Volemos en privado, más nunca en turista" (Let's fly private, never again in tourist). He promises her trips from Cancún to Dubai, Louis Vuitton bags, and diamond rings. It's a huge flex, showing he'll spend any amount of money to make her happy and show her off as "la más chula del barrio" (the prettiest girl in the neighborhood).
But it's not all about the money. He's so into her that he's ready to change his whole life. He offers to delete all the other girls from his social media, saying "Hasta borro las morras que tengo en el Insta" (I'll even delete the girls I have on Insta). He's so swept up in the moment that he jokes about getting drunk and calling a priest to marry her on the spot: "Borracho, llamo al cura y contigo me caso" (Drunk, I'll call the priest and marry you). It's an over-the-top, passionate song about wanting to give someone everything you have.