I read it a long time ago but don't know how to search to find it again. What I remember from the plot: the main dude mas reincarnated or something similar into a world where he has to play death games, he knows of the protagonist and helps him, there is a system of points after each game where the contestants can buy rooms food and other stuff with their points, as the last game they played the werewolf game ( the game where players are secretly divided into two teams: werewolves (a minority) and villagers (the majority). The game alternates between night and day phases. During the night, the werewolves secretly choose a player to “kill”. During the day, all players discuss who they suspect to be werewolves and vote to eliminate one player).