Tozen Ujiie is a Japanese manga artist born on December 24 in Sendai, Miyagi Prefecture. He made his debut in 2001 with the short story Imouto wa Shishunki, published in Bessatsu Young Magazine under the name Ujiie Kunitaka. The work proved popular in reader surveys, leading to a monthly serialization that eventually moved to Weekly Young Magazine, marking his first regular serialization.

Following this success, Ujiie continued to publish manga primarily under Kodansha’s imprints, with works appearing in both seinen and shōnen magazines. His notable manga series include Imouto wa Shishunki, which concluded with ten volumes; Joshi Daisei Kateikyoushi Hamanaka Ai, a six-volume series serialized in Weekly Shōnen Magazine from 2003 to 2006; and the one-volume Idol no Akahon, published in 2006. His longest-running and most commercially successful work is Seitokai Yakuindomo, a four-panel comedy manga serialized first in Magazine Special and later in Weekly Shōnen Magazine from 2007 until its conclusion in 2021, spanning twenty-two collected volumes. In 2022, he began a new serialized work titled Yaotome x 2 in Bessatsu Shōnen Magazine.

Ujiie is best known as the original creator of Seitokai Yakuindomo, which has been extensively adapted into animation. The first anime television series was produced by Studio GoHands and aired in 2010, followed by a second season, Seitokai Yakuindomo, in 2014. A series of original video animations were released between 2011 and 2020, and two theatrical films premiered in 2017 and 2021. Ujiie received official credit as the original work creator for all these adaptations, and he also contributed script assistance and storyboard assistance for the two films.

In his artistic style, Ujiie frequently employs the four-panel comic format. His narratives commonly pair female characters who deliver sexually suggestive dialogue with a male protagonist who serves as a straight man to their jokes. Across his body of work, he maintains a consistent approach where explicit depictions are rare, with recurring visual gags such as identical panel compositions and a distinctive use of sound effects that replace the syllable “n” with “mu”. Character names are consistently written in katakana, often borrowing from the names of professional baseball players. His various series share a connected universe, with locations like Eiryo High School and characters from one work appearing as cameos in another.

Within the industry, Ujiie is recognized for a comedy style that balances risqué humor with an accessible, lighthearted tone. Seitokai Yakuindomo represents his most significant contribution to anime and manga, becoming a long-running franchise with adaptations spanning more than a decade and marking the most extensive animation adaptation of his catalog.