What's your opinion?

[Nickki]

Alright so me and the guy that I have a thing with right now...Im a bit confused and don't know how to handle this..
Im freshman, hes a senior *Yes I know..*
HE has a girlfriend already. I dont.
I know its bad but, I really like him and if he turned out to just be playing with me I honestly say I wouldnt mind it and I would play him back and just have some fun.
We came close to kissing one time..and we flirt like..really hard. He grabs behind me from my waist. He touches my stomach/back/waist/legs alot too. He tells me I'm cute a lot or always complimenting me. He pays attention to the littlest things like when I painted my nails again, or an itty bitty scratch on my finger or arm and ask what happen. Or ask where my binder is if I dont have it in school. He'll notice if Im in a different mood by looking at me. He tickles me alot too. and he held my hand once when we were alone. Otherwise he only grabs my hand. He told me he likes being really close to me. He waits for me. Tell me he missed me and we text everyday. Always has him arm around me too. And we hold our eye contact sometimes too and just look at eachother.
Theres a rumour at my school goin around that I have a boyfriend. But I don't and I know why people think it and its because of him. Numerous people have asked if we're dating but I have to say no. Cause we aren't. AND he has a girlfriend ! He never talks about his girlfriend. Should I bring her up? Be like "So are you and that one girl still dating?" or be like "so how are you and your girlfriend doing?" I'm fine having a thin with him and everything, but its a little uncomfortable that he has one. I want them to break up cause seeing the way he talks to her on facebook or twitter isnt even as close as the way he talks to me. Sorry if that sounded rude..but seriously. Gahh i dont know what to do. and I had a dream the other night about me and him and we finally kissed. Any advice? Sorry its so long..