It's a good thing that he has a doll to live out his fantasies with. Support him in that, and be happy no real women are involved.

Don't ask questions that you can't handle all possible answers to. But now that you've opened that can of worms, what does he do to that poor doll?

ask him if he's into pegging, as its something a doll can't do for him

If he needs a doll for that, then he doesn't need you.

RUN!

At least he's being safe, constructive about his kinks and considerate of actual women? I know it doesn't help with the shock but your bf has Kinks, you can either spend the rest of the relationship pretending he's vanilla or you can take a deep breath and genuinely converse about things. There may even be some the low level stuff you might enjoy. You never know unless you explore. Or you can freak out and run away. He probably should run things past a professional though. If he's just that way inclined then fair enough but if it's caused by childhood trauma or something then it needs a looking at. Up to you really. Is the man worth it? If he's a good bf in all other respects then it comes down to whether you can handle the fact he is not of the 'norm'. Bear in mind that the majority of people with this sort of kink usually repress things and either rot away in their own juices or end up hurting someone. If the relationship is worth it to you then communicate, figure out a comfortable balance and carry on. If he's*not* worth it, however, then run like all ******* hell is on your heels...

Idk, that’s something I personally wouldn’t be cool with but I think different people have different comfort and tolerance levels with their partner being into crazy things. I think it’s good to ask some questions and learn more about it before deciding to dump him entirely.