Zettai Zetsumei Game

Haruma ends up taking part in a mysterious game in place of his best friend. The prize for the winner is 100 million yen. The conditions for participation are: 1) you must be desperate for the money; 2) you can stay out overnight without telling your parents; 3) you must not tell anyone; 4) you don't mind that the loser's life may not be guaranteed. Haruma heads to the venue, but is locked in with the other participants. "I won't lose!" "I'll definitely win!" the boys and girls cried with gleam in their eyes. There can only be one winner. Will Haruma survive this survival game?! (Source: Kadokawa, translated)