Sergeant Manabu guides Group C specifically through their third challenge, "Freundschafts-Verstecken" (Friendship Hide-and-Seek). He oversees the competitive hide-and-seek battle between Group C and Group K within a forest setting. His duties include announcing the rules and explaining critical mechanics, such as the dramatic team-switching option for seekers. He clarifies the immediate game conclusion triggered by a switch within a two-person team, along with the resulting debt transfers: the traitor's new team winning moves debt to the losers, while their original team winning leaves the traitor bearing the losing team's average debt before rejoining. He also enforces restrictions like prohibiting name tag trades during play. Sergeant Manabu facilitates Maria Mizuse's immediate integration into Group C after Yuuichi Katagiri accepts her, despite Tenji Mikasa's voiced trust concerns. He confirms critical game parameters, including the two-hour hiding period allotted to both teams before seekers begin. His role remains exclusively focused on the administration and oversight of this specific game.