Rumbear is a vibrant and informal verb, particularly common in Latin American Spanish, that means "to party" or "to go out dancing." It evokes a sense of lively celebration and enjoyment.
In "Quiere Beber," the word is used to describe the protagonist's intention to forget her heartbreak by going out and having a good time: "Y por eso se va a rumbear" (And that's why she's going to party). It perfectly captures the song's theme of letting loose and moving on from a bad relationship.
"Ella Quiere Beber" is Anuel AA's take on a night out after a breakup. The woman in the song just had her boyfriend let her down, so she goes out to drink and dance to forget him.
Anuel notices her from across the room, and the song follows what happens when she stops holding back. It moves quickly from a party anthem about heartbreak into a much more explicit description of the two of them together, full of the direct, sensual language Anuel is known for.
The recurring "Real Hasta La Muerte" line isn't part of the story. It's Anuel's label tag, a phrase he drops into most of his songs as a stamp on the track.