Never, ever believe rumors. Rumors are nothing but someone starting crap to make themselves look better, or to make another person feel bad. Your best bet is to really get to know this guy, talk to him, and form your own opinion of him from the way he treats you and the way he conducts himself with you. Trust yourself, there are always risks while forming a new relationship, but if you're not willing to take those risks, makes for a pretty boring life!