Chuuya Nakahara is a member of the Port Mafia as well as Dazai's former partner in Twin Dark. He is one of the five Executives in the Port Mafia. He has the Ability named Upon the Tainted Sorrow. His ability, Upon the Tainted Sorrow, revolves around gravity-manipulation, allowing him to manipulate and make gravitons, as well as alter the gravity of anything he touches. He is also capable of standing and walking upside down from ceilings.