In this case, someone who is normal is someone who does not get personally offended when someone criticizes a fictional character. Us humans have a special ability to extend our personalities to symbols, ideas, and even other people. To some people, burning a flag is like burning that person and they get pissed. However, what everyone should keep in mind and realize is that this idea isn't you, this symbol isn't you, this person is not you, and this character is not you. When someone is insulting a game character, they are insulting the game character. There is no reason to be upset if someone doesn't like Serah or Lightning or Crash Bandicoot. It does not mean that they do not like you. Besides, you have much more complexity than Serah, you are able to change. You are able to feel pain, joy, happiness, anger, and all of those things. Serah cannot. She can be programmed to express these, but she is does not actually feel them no matter what you think. You are not Serah.
Because they are not that character, simple as that.
Of course, the criticism could be deeper than just saying shitty. I'd say that these characters are poorly written caricatures with no depth to them. If you think that's a reflection on you, then you can shoulder that burden.