>>49997842
Ever since even the 19th century Koreans were seen as uncivilized, inferior, poor people (and in comparison to Japan, Korea really was a shithole), which lead to an easy justification for the Japanese to occupy Korea and treat the people there poorly. That mindset that Koreans are inferior and uncivilized has persisted until today, but only among Japanese boomers and nationalists. Korea was less advanced, so they're seen as barbaric. They're also next-door neighbors.
Korea also complains that Japan hasn't apologized to Korea, that Japan still uses the rising sun flag, they have territorial disputes with each other, Korean nationalists on the internet insult everything Japanese, they have a huge rivalry in football specifically... which leads to a lot of Japanese naturally being annoyed at Koreans and Korea as a whole.
Young people generally don't care, though. Especially girls. Japanese women love anything and everything relating to Korea and like to learn and spout random Korean phrases. Korean food, music, dramas etc are very popular. Even comics.
Japanese culture and anime specifically is very popular in Korea too and younger Koreans have no qualms with Japan, generally. Popular Korean products, games, etc usually have anime-style illustrations and tropes (See: Blue Archive) and otaku culture is prevalent
