Why...... ?!?!?!?!?

Okay. I'm almost sixteen and I'm a girl. One of my good friends is a 20 year old guy. I have known this guy since he came to our town when he was 7 or something around that age and he used to come over and play video games with me and my brother because we all went to the same school. We are both Christian people just for the record and he's always been a really sweet gentleman and me, michael, and the rest of our family love him to death! (Infact, I have a crush on him, but shhh! lol) I've posted a couple of questions on here like what to do for my 16th b-day party, etc. and if I even mention that I have a 20 year old guy friend, people automatically ume that he's a perv and that I need to stay away from him! It kinda pisses me off and I just wanna know if anyone here knows why people are always hatin on him when they don't even know him?!? He's NEVER been that type of guy...he's friends with pretty much everyone he meets and has never done anything to break anyone's trust.