To make someone your number one romantic focus, your main person. Borrowed from gaming culture where your 'main' is the character you always pick — applied to crushes and romantic interest.

To drop out, step back from something, or quit a situation you no longer want to be part of. From the card game metaphor — when you fold, you're out, and nobody can make you play a hand you don't want.

Infidelity, romantic deception. To put 'cuernos' is to be unfaithful to your partner; to wear them is to receive them.

A guy, dude, or individual — used without strong positive or negative connotation. In Argentina, chabón is the default word for any male person when you don't know their name or just want to refer to them casually.