I used to have a thing for redheads until I married one...now the only good redhead is my daughter.
All jesting aside (I don't really think all redheads are evil), there are people who have a "type" and, in fact, most people do. The type isn't necessarily your own race, culture, creed, etc.
People are attracted to what people are attracted to. Unless it makes you act with some real hate towards those outside your "type" there really is nothing unnatural or wrong about it.
My brother and several other American males (and probably some females as well) share your fascination with Asian women.
I, personally, find most members of the opposite sex fascinating in one fashion or another. Sometimes in bad ways but mostly in good ways.
I have found, for me, that trying to "make it work" with someone I have very little to nothing in common with is self destructive in the worse way.