Touka Takei is a Japanese author and original creator primarily known for work in the light novel and manga formats, with a career spanning from the mid-2000s. Takei began publishing light novel works in 2005 under the Kadokawa Sneaker Bunko imprint, and has also written under the name Takei Toka. During student years, Takei obtained a teaching license in Japanese language.

The most significant and widely recognized work by Touka Takei is the light novel series If Her Flag Breaks, known in Japanese as Kanojo ga Flag o Oraretara. The series began publication on December 2, 2011, under Kodansha Ranobe Bunko, an imprint of Kodansha, with illustrations provided by the artist Cuteg. The series concluded on September 16, 2016, spanning a total of sixteen volumes. The story follows Souta Hatate, a transfer student with the ability to see critical life crossroads represented as flags above peoples heads, who finds himself living in a dormitory with several girls while navigating his own fate.

The success of the light novel led to a significant expansion of the property into other media. A manga adaptation illustrated by Nagian began serialization even before the first light novel volume was published, launching in Kodanshas Monthly Shonen Rival magazine on November 4, 2011. This initial manga series concluded in February 2015, and its chapters were compiled into ten tankobon volumes. Two additional spin-off manga series were also produced: Kanojo ga Flag o Oraretara: O Yusha yo, Flag o Tateteshimau to wa Nanigoto da!?, also illustrated by Nagian, and Kanojo ga Flag o Oraretara: Root Love, illustrated by Kazuki Ayasaki.

An anime television adaptation of If Her Flag Breaks was produced by Hoods Entertainment and directed by Ayumu Watanabe. It aired in Japan from April 6 to June 29, 2014, for a total of thirteen episodes. The series was later licensed for North American release by NIS America. Beyond the television series, Takei was also directly involved in the production of an original anime DVD bundled with the eleventh light novel volume, released on December 2, 2014. For this DVD, which depicted a Christmas party at the series setting of Quest Dorm, Takei personally wrote the original screenplay.

Following the conclusion of the main If Her Flag Breaks light novel series, a sequel manga titled Atarashii Kanojo ga Flag o Oraretara, again illustrated by Nagian, was serialized from April 2015 to June 2016, with its chapters compiled into four volumes.

In addition to this flagship series, Takei created the manga Gakudan!, which began serialization in Kadokawas Comp Ace magazine in April 2015. The story focuses on a high school girl who is followed by the spirit of Beethoven and joins the orchestra club. The manga was illustrated by Anri Sakano. Other notable literary works by Takei include the light novel series Tokyo Emperor Koiuta, which was published starting in 2009.

Recurring thematic elements across Takeis work include romantic comedy and harem scenarios, often incorporating fantastical or supernatural elements into school-life settings. The creators body of work is predominantly situated within the shonen demographic, targeting young male readers.

In the context of the anime and manga industry, Touka Takei is recognized for the commercial success and multimedia expansion of If Her Flag Breaks, which saw a complete light novel series, multiple manga adaptations, a full television anime season, and an original anime DVD, establishing a significant presence across related media formats during the early 2010s.