These replies are intended as a starting point, not to discourage discussion. Further questions, info, and debate are welcome.

"The Japanese ambassador to Germany in 1937 was married to a German woman. Was there any reaction by the Nazis to this?", a reply at https://www.reddit.com/r/AskHistorians/comments/5leo8u/the_japanese_ambassador_to_germany_in_1937_was/dbvvecm/ by /u/inferentialpolice

"How aware was Japan of Hitler's idea of an Aryan master race?" -- it also looks at Hitler's ideas of Japanese -- at https://www.reddit.com/r/AskHistorians/comments/3mi146/how_aware_was_japan_of_hitlers_idea_of_an_aryan/cvf82uv/ , replies by /u/Subs-man and /u/Orchideenpavillon