shortened to , is a Japanese light novel series written by Miku and illustrated by Rein Kuwashima. It began as a web novel that started in the Kakuyomu website in March 2017. It was later acquired by Fujimi Shobo, who have published the series since December 2018 under their Fujimi Fantasia Bunko imprint.

A manga adaptation illustrated by Kazuomi Minatogawa has been serialized on ASCII Media Works' Dengeki PlayStation Comic Web website since December 2019, with its chapters collected into seven volumes as of December 2025. An anime television series adaptation produced by TMS Entertainment and animated by Millepensee aired from April to June 2023. An anime television special premiered in March 2026. A second season has been announced.

Plot

Yūya Tenjō is an overweight, short and meek middle school student who is bullied at school and tormented by his family, except for his grandfather, who is the only person who cares for him. When his grandfather dies and leaves Yūya as the sole heir of his house, his parents expel him from home, and he is forced to live there alone. Inside his grandfather's house, Yūya discovers a portal to another world named Argena, where he obtains power that will change his life forever as it leads him into battle against multiple powerful malevolent entities, demons, extraterrestrials, and even gods, sometimes for the sake of the very fabric of existence itself, in the past, present and future.

Media Light novels Written by Miku, the series began publication online in the Kakuyomu website on March 25, 2017, under the tentative title . The series was later acquired by Fujimi Shobo, which began publishing the novels with illustrations by Rein Kuwashima starting on December 20, 2018, under its Fujimi Fantasia Bunko imprint. As of September 2026, twenty-one volumes have been released.

In September 2021, Yen Press announced that they had licensed the novels for English publication.

A spin-off series titled , written by Ryō Kotohira and illustrated by Kuwashima, began publication under the Fantasia Bunko imprint on December 20, 2022. As of May 2024, five volumes have been released. Its plot deals with Princess Lexia's impulsive decision to engage in a "learning journey" throughout her world in order to become Yūya's equal, and she ends up gathering her own experiences to help her grow into her own.

On February 20, 2025, another spin-off story was released. Titled , and also written by Kotohira and illustrated by Kuwashima, its plot details Kaori Hōjō encountering a magical girl named Noah and discovering her own magical power hidden within herself in the course of her adventures with her. A sequel volume was released in July, 2025.

Main series

Spin-offs Girls Side

The Story of Kaori Hōjō

Manga A manga adaptation illustrated by Kazuomi Minatogawa began serialization on ASCII Media Works' Dengeki PlayStation Comic Web website on December 13, 2019. As of December 2025, seven volumes have been released. Yen Press has also licensed the manga in English.

A manga adaptation of the spin-off series Girls Side, illustrated by Miinosuke Seo, began serialization on the KadoComi and Nico Nico Manga websites on April 25, 2024. As of January 2026, three volumes has been released.

Main series

Spin-offs Girls Side

Anime In August 2022, an anime television series adaptation was announced. It is produced by TMS Entertainment and animated by Millepensee, with Shingo Tanabe directing, Shin Itagaki serving as chief director and supervising the scripts, Hiromi Kimura adapting Rein Kuwashima's character designs for animation and serving as chief animation director, and Akiyuki Tateyama composing the music. The series aired from April 7 to June 30, 2023, on Tokyo MX and other networks. The opening theme song is , performed by Tsukuyomi, while the ending theme song is , performed by Shikao Suga. Crunchyroll is streaming the series along with an English dub. Muse Communication licensed the series in Asia-Pacific. The initial streaming of the series' 13th and final episode was inexplicably delayed by two days from the original June 26, 2023 release date, which ended up airing on June 28 instead.

A new anime project was announced during the "Fantasia Bunko Daikanshasai Online 2023" livestream on October 14, 2023, which was later revealed to be a television special, with Itagaki serving as director and Kimura returning as character designer. It premiered on March 31, 2026.

A second season was announced at AnimeJapan on March 28, 2026.

Episodes

Television Special

Game A free-to-play MMORPG browser game, titled I Got a Cheat Skill in Another World and Became Unrivaled in the Real World Too: Parallel Universe, was announced on March 17, 2023. It will be launched on the G123 platform in multiple languages.

Reception In May 2018, the web novel won the Grand Prize at the 3rd Kakuyomu Web Novel Contest in the Science Fiction/Modern Fantasy Division. By October 2023, the series had 3 million copies in circulation.

See also The Fruit of Evolution – another light novel series by the same author

Notes

References

External links at Kakuyomu