Those movies are not free and that's the point. Torrents as such are not illegal, those are just the means. What IS illegal is downloading copyrighted material without paying for it, no matter how and where you download it. So if it is something that is sold in any store (online or in physical stores), you can bet that downloading it for free is a crime. Be it via a torrent or any other channel.
It doesn't matter where the movies come from, Korean movies are copyrighted too. You may be less likely to get busted...