As a Black man who not only has been to Japan, but has also had dealings with Japanese people for the past 15 years:
-- Japanese people on the whole are more ignorant than outright KKK-type racist, especially to Black folk
-- If Japanese people ARE racist, it's towards Koreans and Chinese (and perhaps other southeast asians, like Filipinos, who they tend to look down on). They don't look at us in the same fashion as White people look at us. It's like a curiosity
-- Their country is something like 98% them, where they all speak the same language with (minor differences, outside of Okinawa). This means, not just Black folk, but any other group of people stick out like a sore thumb. Because their culture is about collectivism and focusing on the group, western people can't handle it. We're so caught up in sticking out and trying to be expressive, when you got 150 million people trying to fit in. There's going to be some clashing there.
-- If you speak the language, YOU'RE IN. They open up to you like a fukking children's book. To be clear, to them, you'll never be Japanese (I've had girls call me a "gaikokujin" while they were here in LA lmao. That word means foreigner), but you'll be in the group. Absolute dime pieces will be available to you, and they have incredible personalities.
That's been my experience.
Living in Japan while Black can be difficult if you're not trying to fit in and if you refuse to acclimate to the culture and language. You might also run into some issues with people thinking you're a tout. The African touts over there are particularly aggressive-- nikkas grabbed my arm and tried to drag me into a club fam
Nikka, I am 6'1, 6'2" on a good day, and 215, but they ain't even scared to walk up to me and grab me. They gotta stop that shyt mane. I almost busted that dude head wide open