As an older guy who dated a girl who was (too) young, maybe I can give 'the other' perspective.

First off, I object to many posters calling your guy a 'predator' right off the bat, because it insinuates that he purposefully seeks out younger girls because he knows he can manipulate them. I seriously doubt that is the case; I'll explain in a bit.

Secondly, I think that age gaps in general are frowned upon a lot more than a few decades ago, even age gaps where teenagers are involved with 20 or even 30 somethings. In the 60's it seems that is was accepted-- or at least tolerated a lot more than now. I don't know what's right, but I do think that these days a lot of people take offense at this sort of stuff when there might not be that much wrong. People are overly politically correct, and quick to judge, hiding behind 'saving people from getting hurt'. There are many 16 year old girls who are more equipped to be in a healthy relationship than when I was 25.

Having said this, however, I do regret dating the young girl, even if it was very short lived. There are a few reasons why I regret it: I now know, that if you want it or not, there is a power inequality. Much like a doctor and his patient. I didn't realize it, but it was true that I could have done or said things (consciously or subconsciously) that would have emotionally blackmailed her, simply because I'm older, have money, have experience, and so on. She might not have felt it, but it's just a dangerous situation.
Secondly (and this goes back to the predator-point), I was immature, and incapable of having a mature relationship. I did not consciously seek out young girls, but it felt like I had a lot in common-- and I'm a bit ashamed that that was the case, but it was. It stems from insecurity and bad relationships-- I couldn't have a relationship with a peer, because most of the time they were (mentally) a lot stronger than me. Again, this is all hindsight.

Before that, I dated other girls who were mentally young and not as strong-- but they were my age. There's the danger: I needed to grow up, take responsibility, in all aspects of life, so that I would be able to date girls my age-- or at least, responsible and strong women. Ironically, the episode with that girl made me realize that, and I've worked hard to make it happen.

Your guy might very well be like that: for girls his age, he's basically too weak and immature-- girls his age scare him. The fact that he gives in when you wanted sex (I read somewhere in the comments) supports it: he's not strong enough to stick with his opinion or stance. And if you're unlucky, and shit hits the fan, he might blame you for seducing him (if that happens btw, remind yourself that you are never ever responsible for his actions). This is not because he's evil, but because he is weak.

I can't tell you what to do, however. It might work out-- it sometimes does. But I think the majority doesn't. And it's possible that you might have to be the responsible one in this relationship.