Should I hang out with him or not?

There's this guy in my school he really doesn't have friends or anything he is pretty antisocial and I have my friends who arnt interested in him but the other day he dropped down the stairs and I helped him and then he said can we hang out on Saturday and I said I'll see... I was thinking about going for a pizza later with him but should I???????? Or not at all? Or do something else? Help please thanks (by the way please don't say we should go out or anything I've Been with my boyfriend for 2 years and I plan to stay with him too) I'm 17 & this guys 16