Yuki Yuna is a Hero -Chapter of Washio Sumi- is based on the illustrated novel series Washio Sumi Is a Hero, set two years prior to Yuki Yuna.
Kara Dennison is responsible for multiple webcomics, blogs and runs interviews for (Re)Generation Who and PotterVerse, and is half the creative team behind the OEL light novel series Owl’s Flower.
The trailer also includes a piece of Suzuko Mimori’s theme for the film, “Sakiwafuhana.”