Drama about characters with an unexpected fetish

I am already aware of Japanese series portraying characters who are kinky or harboring a fetish. Now I’m just curious about c/k- drama with characters  who are serene or normal on the outside, but only discover their own hidden fetish when they become passionate about their love interest. F.e. Wei Wu Yi in Sound of the Desert, or novel version Lan Wang Ji in The Untamed who both like to bite their partners when kissing. 

 mahiba:

The beauty Inside, second couple, they act like a very traditional couple with strict gender roles, except the roles are reversed. She's very overbearing and protective and he acts in a more submissive way. Except that it's kind of role playing, he's not really submissive at all but let her get away with it. 

The Love Knot; it really boils down to a single scene when she comes over and it's implied that he's so hot and bothered that he needs to go to the bathroom... 

Too Late to Say I Love You; he's a general but acts really nicely and gentlemanly while he's trying to woo her. Then when they get together he's revealed to be a very rough lover. No violence, but multiple love scenes show an almost desperate passion from the ML. 

Your question made me realize that Japanese dramas tend to have a lot of those characters with a hidden fetish, but not  lot of chinese or korean dramas do. Does anyone have an idea of why that would be? 

Thnx for the recs! Agreed, there's really a difference between Japanese dramas and others. Who knows why?

@usna Thank you!  I haven't seen 2gether yet, and I will rewatch the other BL series.