Seon-U Kang, a high school student, single-handedly takes down a group of illegal loan sharks who show up at his house. While being treated at the hospital, he encounters a mysterious man who offers him an invitation to a suspicious secret fighting tournament with a massive cash prize. The prize money is his only hope to save his family. Seon-U must survive in the combat ward at all costs! Will he be able to defeat all other fighters and become champion? (Source: WEBTOON)