Aggressive cat!

[mwrcook]

Hi there,

I have an aggressive cat situation, my room mate whom I have lived with for three months has an aggressive mixed cat (we think some sort of siamese with a tabby but aren't quite sure) He has hissed at me, and tried to scratch me numerous times, actually almost everytime he sees me. I have never been mean to him, I try to give him treats and he hisses, he is almost 2 years old, and is indoors, he does have very little toys that I have discovered. I was wondering how to go about this?

thank you very much!