Asatte no Houkou.

Asatte no Houkou was written and illustrated by Yamada J-ta, originally serialized in the Japanese magazine Comic Blade Masamune between 2005 and 2006. The story centers on the unexpected physical transformation of a young woman and a young girl, who are magically aged and de-aged respectively, forcing them to confront their personal emotional baggage and maturing processes. This title belongs to a period of Seinen manga that frequently explored themes of psychological growth through fantastical narrative devices.

The work gained enough traction to be adapted into a twelve-episode anime series produced by J.C.Staff, which premiered in 2006. Yamada J-ta's art style is characterized by a delicate, soft aesthetic that reinforces the series' focus on nostalgia and the complexities of familial relationships. While not a massive commercial blockbuster, the manga is well-regarded among enthusiasts for its intimate storytelling and the thoughtful, grounded way it addresses the contrast between childhood innocence and adult responsibility.