The Ones Within English Subbed

Iride Akatsuki is a popular game footage uploader. He wakes up one day to find that he's been kidnapped and taken to a strange place, along with a number of other uploaders who specialize in different genres of games.

A mysterious alpaca-headed host gathers them after the initial stage, to explain how the game will proceed. Will the group of gamers clear the game and make it back to their real lives?

(Source: Kirei Cake)