The Saga of Tanya the Evil, known in Japan as Yōjo Senki , is a Japanese light novel series written by Carlo Zen and illustrated by Shinobu Shinotsuki. It began serialization online in 2010, on the user-generated novel publishing website Arcadia. Enterbrain acquired the series in October 2013 and has published fourteen volumes by September 2023. A manga adaptation with art by Chika Tōjō began serialization in Kadokawa Shoten's Comp Ace magazine from April 2016.

Enterbrain (エンターブレイン), formerly Enterbrain, Inc. , is a Japanese publisher and division of Kadokawa Future Publishing founded on 30 January 1987 as ASCII Film Co., Ltd. . Magazines published by Enterbrain are generally focused on video games and computer entertainment as well as video game and strategy guides. In addition, the company publishes a small selection of anime artbooks. Enterbrain is based in Tokyo, Japan, with a paid-in capital of 410 million yen. Enterbrain's current president is Hirokazu Hamamura.