To look, feel or act in a way that suggests you are considering taking part in the inexcusable act of rape.
The word "Rapey" can be used to describe how a person is dressed, if they are wearing clothing which suggests that they could be considered a predator to women. This could consist of, but not limited to, collared polo's and kakis.
When using the word "Rapey" to describe someone's actions, would indicate that the person is acting like not only a douche bag, but that they are either rubbing themselves up on a girl without permission or doing other rude actions. (Also, drugging someone or dragging them into you vehicle are considered "Rapey" behaviours.)
If a person is standing at a party and stare at the same girl for 3 hours straight and refuse to stop smiling in a meme-like way, they can be considered to look very "Rapey." Someone's smile, creepy eyes, or dance moves are also examples of things they can do to seem "Rapey."
"Hey Mike, fix your face, you're looking pretty rapey
"Go change that rapey
"You are no longer just a douche-bag
you have officially graduated to a rapey