Fetish is a nasty word. When you say a "fetish" you're referring to an object.
What is an object? Obviously: has no soul, no heart, no mind. And therefore, cannot be treated like a person.
So if a guy tells you now that he has an Asian fetish? You know. It means that he's attracted to what he thinks Asian girls are, not WHO YOU ARE.
Asian fever is when this happens in a widespread way. Usu. they see porn and you know, they start thinking it's like that but a lot of times it's not.
Then, what is objectification? Objectification is a terrible term.
It goes both ways. It means using a person for sex without regards to them as a human being, or targeting them for violence (when they did nothing wrong).