I'm going to quit my job because my boss watches anime.
That can't be the real reason. How do you know your boss watches anime?
I saw him watching it.
Your boss watching anime is a silly reason to quit your job. Keep your job and stop worrying about what your boss watches.
I don't care and I deserved a better job anyways.
Sounds like you were finding an excuse to leave, I believe you should have left a long time ago then. But don't you think it's a bad idea to judge people by what they watch? Anime can be really fun, why don't you try picking up a series?