Bellaqueando comes from the word "bellaquear," which is a Spanish slang term. It refers to flirting or engaging in playful, often sexually suggestive, behavior.
In the context of this song, the artist sings, "Y yo aquí contigo, bellaqueando contigo," meaning "And I here with you, messing around with you." It implies a casual, intimate encounter that goes beyond just friendship, highlighting the complicated relationship dynamic in the lyrics.
"Amiga" is Dalex singing about getting tangled up with a close friend right after a breakup. He thought he was over his ex, but her late-night texts pull him back in even while he's falling for the friend who was there for him.
The song moves between guilt and desire: he doesn't want to hurt his friend, he admits he's started to care for her, but he still can't fully let go of his ex. By the end he decides it's better to walk away than keep hurting someone he genuinely loves as a friend.