In Japan, South Korea is now cool. Speaking and singing the local lingo, Korean popstars like Girls’ Generation rule the charts and appear on Japanese variety shows and in commercials. It wasn’t always that way.
https://lastchance.cc/2010-the-year-korean-pop-burst-japan-5718647%3C/a%3E%3C/p%3E
Historically, slurs against Koreans are some of the words banned from Japanese television broadcasts.