When Gran Marsenal Empire started the invasion into Mismarca Kingdom, the King of Mismarca entrusted the country to his son, Prince Mahiro, to discuss an alliance with the Republic of Zepilm. At the same time, the Empire's third princess is closing in to the Mismarca Kingdom...

Kawamura Hideo, a typical ordinary guy with no job, he came to Tokyo searching for jobs, he sent a total 34 job applications to only failed at the first hurdle (all of the companies didn't even ask him to attend an interview). Feeling rejected, he became a hardcore hikikomori and shut the world around him, his parents also won't send him money since then. When he starved to death without any money, lost hope and would decide to go just die he found a computer on the street (containing Will.CO21 virus) and took it home.

He found a way to participate in a martial arts tournament "Holy Devil Cup" from that computer. Where the winner could get the power to rule the world, martial artists, soldiers, vampires, Majin - all 3024 participants gather there. Now what Hideo would do to win this mad tournament...