In the aftermath of the Kagutsu Crater Incident fourteen years ago, Tenkei found a young Nagare under the rubble, whose heart was pierced by a stone. However, a green light emitted from Nagare and a Sword of Damocles manifested above him. In the present, Tenkei claims that he is no longer Seigo Ōtori the Sixth and Gray King, but rather the freeloading surrogate father of Nagare...