Mokumokuren is the manga creator behind the series The Summer Hikaru Died. The artist made their professional debut with this work, which began serialization on Kadokawa’s Young Ace Up website in August 2021 after initially sharing related illustrations on social media. The creator’s pen name is shared with a figure from Japanese folklore, a yokai known for inhabiting old shoji screens, but the person behind the manga maintains a private identity, often appearing at public events with their face concealed.

The creator’s artistic identity is closely tied to The Summer Hikaru Died, a horror and coming-of-age story set in a rural Japanese town. The series follows Yoshiki, a teenager whose best friend Hikaru dies but returns in the form of a doppelganger entity. The central relationship explores themes of loss, identity, and the complexities of connecting with an unknowable being. Mokumokuren has cited several influences on the work, including the psychological depth of the manga Tokyo Ghoul, the tone of the Silent Hill video game series, and the philosophical concept of the Swampman thought experiment. Growing up in a city but spending time in the countryside with their grandparents, the creator drew on those experiences to craft the isolated village setting. The author has stated that the goal was to create a horror story focusing on the emotional struggles of the monster itself, balancing suspense with the psychological development of the characters.

The Summer Hikaru Died quickly achieved commercial and critical success following its debut. The series topped Takarajimasha’s This Manga is Amazing! list for male readers in 2023 and received nominations for the Manga Taisho awards. The work and its creator were also nominated for Eisner Awards in the Best Writer/Artist and Best U.S. Edition of International Material—Asia categories. Within months of its release, the first compiled volume had sold hundreds of thousands of copies, with total circulation later reaching into the millions.

The property expanded with a light novel adaptation in December 2023, followed by an anime television adaptation. The anime, produced by CygamesPictures, premiered in the summer of 2025. Mokumokuren participated in the production of the anime, collaborating with the production team to ensure the adaptation preserved the core elements of the original work. The creator has mentioned interest in writing a fantasy story for a future project but remains focused on the ongoing manga series, which was planned to span approximately ten volumes.