The Trials

In 3023, the entire world has been overpopulated. The amount of births in a year is 12 million and up, so, for the world population control, the nations came together and made a law named "The Trials". People from the ages of 12 to 25 must participate in the law. They are taken to a secret bunker and have to play games. Saori, who is 20 years old, did not want to be chosen. However, Saori volunteered to play in the law during the reaping time to save her sister. Will Saori survive? How will it all go down? Who will survive? And, most importantly, who is the mastermind behind all of it?