Do you know what a fetish is? Let me educate you why its probably not.
Firstly, the author may write bls about subjects they are familiar with - for example they may have studied medicine at varsity and have a background in the subject matter.
Secondly, they may receive instructions on project they write about - their editor may have given them the work. Its a job.
Thirdly, they may decide to write about a topic they know will sell - it does not mean they are obsessed with that topic . It means they are making a business decision and giving audience what they want.
Also want to add that being interested in a subject matter in fiction does not mean you have a fetish. Its means you have a preference for that type of genre.
In my case i love reading toxic material and toxic romance and non con. In reality non con and toxic would repulse me and i would see it as a criminal offences.
I did research to find out if noncon that was my fetish. What i have is described as a psychologically mechanism for exploration and escapism.
I HOPE THIS HELPS OTHERS
"A true fetish typically demands the real-world presence of the object or scenario to function. If the mere thought of the real-world scenario is repulsive or unwanted, it confirms the interest is likely a fantasy preference rather than a compulsive fetish."

I think the author has doctor fetish lol (≧∀≦) i wish them luck go and make the asian mama proud