Churro literally refers to the popular fried-dough pastry, often dusted with sugar and cinnamon. It's a delicious and recognizable treat in Spanish-speaking cultures.
However, in this song, YSY A uses "rellenando como un churro" (filling it like a churro) in a slang context. It implies that the house is being filled to the brim, or perhaps even overstuffed, with something valuable or illicit, much like how a churro can be filled with dulce de leche or chocolate. This clever double meaning makes the word memorable and adds a layer of intrigue to the lyrics.
YSY A's "SEA LA HORA QUE SEA" is all about that non-stop hustle and grind, no matter what time it is! He's got messages piling up, but he's too busy making moves. He says, "La beba quiere que la lea y yo que no leo ni lo que pago" [The girl wants me to read her messages, and I don't even read what I pay for], which is a pretty funny way to say he's got bigger things to focus on.
The song really emphasizes the idea that there's always something to do: "Hay que terminar la tarea / Re-stockear la heladera / Hacer los flow' que tararean" [You have to finish the task / Restock the fridge / Make the flows that people hum]. It's about working hard, staying productive, and making sure the money keeps coming in, even if it means staying up late. YSY A is basically saying, don't look at the clock, just get it done!