I'd be extremely cautious to get involved with a guy like this. If he has a lot of girls with 'crushes' on him, there is a good chance he's not looking for anything serious (although you never know). If you are scared of this guy, if he's loud and aggressive, trust your instincts and keep away from him unless he can behave in a civilized fashion for starters.
It might sound old fashioned, but your best option in a case like this is definitely play 'hard to get'. If he's really interested in you, he'll let you know. Even then, just take your time to make sure if he's genuine or not. If he's not he'll move along and that will be your lucky day.
"The only thing to do with good advice is to pass it on. It is never any use to oneself." - Oscar Wilde