From [MangaHelpers](https://www.mangaupdates.com/groups.html?id=1011): A mysterious event causes a number of people in Ikebukuro to collapse, but after they gain consciousness they explode and die! Ryuji and his friend Taizou Miyauchi are determined to find the cause after their friend meets their explosive end in front of them. But instead of finding answers, they are given a death sentence and transported to a strange world by a mysterious child. To return home they must compete in, and survive, the Purgatory Games! [Niffer]

Yuu Kaneko has lived his whole life on a small, peaceful island, and he wants nothing more than to leave it behind for Tokyo and the big-city life. But one day, that peace is shattered when his fellow islanders are mysteriously infected and start to tear one another apart! Those afflicted regenerate at inhuman speeds, even growing back severed limbs, and nothing seems capable of stopping them. As the numbers swell, how are the few left unaffected going to survive…? (Source: Yen Press)