Forced to make a choice to save his companions, Keisuke selects Byakuya Rinne as the "keyhole" for a brutal trial. While the act begins with violence and a desire to break her spirit, Rinne's unsettling composure leads to an unexpected shift toward mutual intimacy during their break. As they navigate the game's psychological traps, Rinne reveals a mysterious perspective on their situation and her role as the "mother of the savior."