On the night of his 30th birthday, one man’s dreams of wielding magic come true after he unexpectedly passes away. He wakes as Sion, a young child in another world. He and his elder sister, Marie, are the children of a lower-class noble family who govern their region. After receiving conflicting messages from their father, Sion and Marie set out on an adventure to uncover the magic.
Marie absolutely adores her younger brother Shion, everything from the way he secretly plays pretend to the oddly grown-up look he gets sometimes. One day, he asks their father about something called "magic" and their whole lives change.