How can I deal with a gay guy that's pursuing me when I'm straight?

I don't want to hurt his feelings and I might want to join his frat but that's not too likely now, but anyways like he asked to suck me thursday and i didn't respond and i was supposed to meet his frat last night but i didnt and he sent me a message today, like he wants to study together or something, so i dont know if doesn't know i'm not interested or what, or if he wants to be my friend now, it is still very uncomfortable for me so should i respond now or what; and if so how should i word it