It

A pronoun used to refer to an object, however some people prefer to use this pronoun (as opposed to he or she)

Example with an object.

"What do you think of this sweater? Dows it make me look fat?"
"I really like it."

Example with a person.

"What do you think of Reggie?"
"I really like it."

Fuck boy

A dude who is only in a relationship for sex. He’s a sex addict, collects nudes.

Alternatively: a man who you only date for sex. You know there’s nothing there, but it can be fun while it last.

Person 1 “You know he’s a fuck boy, right?”

Person 2 “Yeah, I’m only in it for the dick anyway. I’ll be the one to dump him when I get bored.”