Naka no Hito Genome (Jikkyouchuu)

is a Japanese manga series by Osora, serialized online via pixiv Comic website since 2014, and has been published by Media Factory. An anime adaptation by Silver Link premiered on July 7, 2019.

Plot
A series of strange disappearances have been occurring throughout Japan, and despite the police's efforts, no leads have been found apart from the fact that all of the victims were youths. A popular "Let's Play"  tuber named Akatsuki Iride gets caught up after one upload consisting of a F2P game called "The Ones Within - Genome". Although online rumors claim that the game causes anyone who clears it to disappear, Akatsuki is wholly unaware until the rumors prove true -- he is summoned to a completely different world, and meets other teenagers like him: Karin Sarayashiki, Kaikoku Onigasaki, Himiko Inaba, Anya Kudou, Yuzu Roromori, Zakuro Oshigiri, and Makino Aikawa.

The eight teenagers are welcomed into what is known as the 13th Avenue, headed over by a strange man with an alpaca mask calling himself "Paca", and are informed of their task: to work together in clearing stages of the game and retrieving the "chromosome", a keycard-like token of completion, to subsequently reach 100 million viewers in this live stream where death and injury can all occur. Resistance is not tolerated; those who do are imprisoned in what is known as the "White Room" to wait alone for the rest in the Avenue to complete the game. Henceforth begins their trials in clearing this game, but what lies in wait for them is not only dangerous obstacles, with each member having a hidden past and dark secrets of their own.