The Japanese are perhaps the world’s most unashamed racists. They look upon some races as worthy of emulating (Caucasians) and others as simply inferior. Africans are in the latter category. Mixed race, Japanese and Caucasian or Japanese and Korean or Chinese, girls are popular as models and seen as quite exotic. But they are not considered truly Japanese. Even Japanese who have spent time overseas and picked up western attitudes like individualism are “henna nihonjin”, or “Strange Japanese”.
Japanese from the main islands don’t consider Okinawa Japanese as “pure” Japanese. Rural people don’t usually mix with city folk.