What to do about not having sex?

Tell him that that you are uncomfortable and don't want to do that if it makes you uncomfortable, most guys that do that when they first meet you are only looking for one thing, you don't wanna be with a guy like that, he'll just hurt you emotionally and make you do things you don't want to do.

Seriously, too late now. If you let him do it once, he will figure he can do it again, next time he may even think it's ok to go further.
Also, advice for the future. If they start humping you within the first few times of meeting you, they only care about having sex.
Be smart and set the rules out from the beginning; as soon as you feel uncomfortable, tell the guy. After the second warning, ditch the player. Cause that's all he is.

Next time, maybe you can just take his hands out from under your shirt and hold his hand while you guys make out instead so its not like your completely shutting him down.

Be assertive and tell him to get off, but you have to mean it and not sound unsure because he will assume you are playing hard to get. Guys often take no for yes, so you have to make sure you are firm in your no and that he knows you mean business. If he won't leave you alone or you make out again and he feels you up then it may be time to get someone bigger then him and older involved, not a parent because that's just awkward but someone you trust. Believe me I have been in your shoes, I was a little older but I let him feel me up any way and I still get an icky feeling when I think about it, and that was almost seven years ago...so think about how you will feel even in a few months.

Don't be alone with him. Period. You've already let him touch you're tits and he'll try to do it again. If you can't even tell him to stop groping you, then much more stuff is going to happen and you'll feel even worse when that happens, so just stop now. You don't need to be around him at all.

You are not being rude by telling him to stop, he's is being the rude one by not respecting your feelings. If you do not plan having sex soon, then you need to tell him to stop, because if you let him, then he'll figure you want yo go all the way.