Diarmuid is the son of Donn, foster son of Aengus Óg, and first spear of the knights of Fianna. He is known as Diarmuid of the Love Spot (ディルムッドの愛の黒子?), due to a magical love spot granted to him by a young girl. Any woman who gazes upon the spot. A knight whose love and loyalty were tested throughout his life.