In my experience, they hate Chinese more than Koreans most of the time. Korean culture is a bit closer to the Japanese one, so they are seen as less crass and disrespectful than Chinese. Also Korean idols are really popular which contributes as well. Also worth noting that Chinese people are the majority immigrant by a lot. However, I suppose your mileage may vary depending on who you're talking to.

I can concur that as a foreigner, you'd better not try anything illegal if you intend to stay there though.