No, it's more than fucking reasonable. That person is just one more asshole who can't understand that just because you write about a kink doesn't mean you'd indulge it in real life. And your notes and tags more than show what the story is going to be like...it was their fault for reading it. Don't worry about it, hon, your story is damn popular, that negative comment is like a drop in the ocean of all the positive comments. *Hugs*

xx