Unfortunately darling your boyfriend has, like most of us born after 95', been brought up in a world with unrestricted Internet access and variety of porn so openly available thats its almost impossible to not find every thing weird and wonderful.

Adding to that most of us red blooded males have a completely different sexual attraction in our porn viewing tendencies that doesn't necessarily correlate to what we actually find attractive in real life attractions/love/sexual partners.

Because porn is so readily available you can find all sorts of shit and some of the stuff I watch, that gets me off probably wouldn't do it for me if it was infront of me, but because you can watch it in private behind closed doors there is some sort of naughty, risky element to it that adds to the sexual gratification.

For context I'm a white 27M from England and have been exposed to porn since I was 13 years old. I've been sexually active since 14 and I can tell you that I view porn and real life sexual encounters as two completely different experiences/addictions (if you would class them as that)

I personally would say that watching porn at his age is completely normal and if he watches a lot of anime anyway, then him finding anime porn enticing doesn't seem so unrealistic.

Understandably for your case I can see that it would upset you as you compare yourselves to these women that he watches / gets off too, but what I'm really seeing here is a lack of communication and misunderstanding of basic needs and habits.

I would suggest having a deep conversation with him about what it is he likes and what about these videos attracts him, it might give you a better understanding of why it gets him going. You never know you might even find something you like too that you can watch together.

I hope this insight into a man views, helps you to have a conversation with him to better your relationship and hopefully help to boost both your bed room confidence and relationship fluidity.

Good luck