See the little button shaped like an x? If you don’t like someone, click that button on their post. Instead of starting fights and hurting feelings, you could very easily just do that.
For example, “As a writer, I feel offended by fictionkin. I hate them and don’t want them to exist. I feel obligated to tag my hate.”
Yeah. Just click the button. Don’t start a war. They tagged the post for whatever reason, but that doesn’t mean you need to try convincing them of your beliefs. They’re likely not going to budge and suddenly think, “Oh, yes! I instantly am okay with this strange belief that claims they are a fictional character that I know and love!”
Be the better person and
I can almost guarantee they won’t accept anything you tell them.