mr. tell it

To cockblock a guy by telling the girl he's a fag, douche, player, or any other insult to help discourage that girl from liking him.

Jake: You shouldn't get with Zach, he's a douche and a player and he's only going to use you
Girl: What? What are you talking about?
Jake: He's a dick, don't hook up with him.

*next day*
Zach: Wow, Jake is a mr. tell it. What a fag.