"Korean love Japan" is "일뽕"(il-ppong) in Korean.
The longing to Japan, Japanese animation and culture, product, that Korean love such things called "Ilbbong".
Unlike pro-Japanese present in the older generation, many younger generation such as teens.
일뽕 is, 일본 (Japan, Ilbon) + 히로뽕 a synthetic language (Hirobbong, a kind of drug), refers to a human that has been poisoning in Japan.
Against Ilbbong, blindly patriotic behavior is called as 국뽕 (Gukbbong), it is an abbreviation of 국 (country) + 히로뽕 (Hirobbong).