According to Statistics Korea, the national statistics office, the unemployment rate last year for people aged between 15 and 29 was 9.5 percent, compared with 3.8 percent overall and 3.6 percent for Japanese 15 to 24.
Also, Japan has a vocal far-right fringe, but the average Japanese person has no qualm with Koreans and Korean TV, music, food etc is widely popular. There are over 500,000 Koreans living in Japan, many 2nd or 3rd generation, and plenty more naturalized Japanese of Korean descent. If anything, I'd suspect there's a lot more antipathy in Korea towards Japan than the other way around...