@Babaoo  surprisingly it's a mirror in real life. 

A few years ago I was dating a Korean girl (I'm a dude) and I had to break up with her because after a year, every time we had sexx she would scream at me to stop. And when I did she got angry that I stopped.

The more I dated her and the more I talked with her friends, the more it felt like some asians have this weird concept of purity and innocence that if they don't complain while having s** it's as if they're used to it, and that means they're easy or slu***.

I thought it was weird but when I told my friends why we broke up, there were more than 4 in our group that had an experience like that.

And I never noticed it before my experience, but even in their pòrn the woman/or bottom act as if they're in pain or being taken by force. 

So yeah, I think there's a reason why in every single BL and straight manga the FL or uke complain and at least scream once  to stop. Cuz literally is in every single one.