Beyond the Boundary: Daybreak

境界の彼方 ＃0「東雲」

Set years before the main series, this prequel OVA follows Hiroomi Nase as he sets out to subdue the half-human, half-youmu Akihito Kanbara. His curious younger sister Mitsuki tags along, and the siblings meet Akihito for the first time, only to realize others are hunting him too. The episode fills in how the Nase family first crossed paths with the boy whose youmu nature later anchors the story.