The Testament of Sister New Devil (Japanese: 新妹魔王の契約者(テスタメント), Hepburn: Shinmai Maō no Tesutamento) is a Japanese light novel series written by Tetsuto Uesu and illustrated by Nekosuke Ōkuma. Thirteen volumes have been published by Kadokawa Shoten since 2012 under their Kadokawa Sneaker Bunko imprint. A manga adaptation has been serialized in Kadokawa Shoten's Shōnen Ace magazine since May 2013. A second manga adaptation has been serialized in Hakusensha's Young Animal Arashi magazine since February 2014.
The first season of an anime television adaptation premiered on January 7, 2015. The first OVA episode was released on June 22, 2015. The second anime television season premiered on October 9, 2015. A second OVA episode was released on January 26, 2016. A third OVA episode was released on March 28, 2018.
Contents
Plot
Basara Tojo is a high school student studying at Hijirigasaka Academy when his father Jin suddenly gets "remarried" and asks Basara if he wants to have sisters. Basara meets his two new, cute stepsisters, Mio Naruse and Maria Naruse. After his father departs overseas, Basara quickly finds that the two sisters are actually part of a demon clan, and he is meant to be with the hero clan. Mio, a Demon princess, forcibly attempts to make a master and servant contract with Basara, but Maria has it end up being the opposite, with Basara as the master. Basara then keeps getting into etchi scenarios, largely to protect Mio from being pursued by other demons who are after her heritage, which is passed down from the former Demon Lord Wilbert.
Characters
Main
Basara Toujou (東城 刃更, Toujou Basara)
Voiced by: Yuichi Nakamura (Japanese); Chris Hackney (English)
Basara Tojo is a Year 1 high school student at Hijirigasaka Academy and the protagonist of the story. As a member of a hero clan, he grows up in a hidden rural village. Basara wields the formerly cursed sword Brynhildr. Basara is the only son of Jin Tojo, formerly acknowledged to be the 'Strongest Hero' in the village. As Jin's son, great things are expected of Basara and he is unusually strong even as a youth. Basara possesses the skill 'Banishing Shift', which nullifies any skill directed against him. Five years earlier, when Jin is on a trip, the seal of the S-Ranked 'Evil Spirit' is broken. Many people, including his friends and family, are killed by the spirit. When he sees the Evil Spirit trying to harm his childhood friend, Yuki, his Banishing Shift goes out of control, causing a great crater to form, obliterating the bodies of those slain except Yuki, and also cleansing the area of the evil spirit. Yuki is spared and the cursed sword Brynhildr is cleansed. Because of this, he is confined in the village and when Basara's father returns he insists that Basara be released, which he is, but only on the condition that Jin lose his title as a hero. Jin chooses the release of his son and they move to the city. In the present, Basara's father tells him that he is remarrying and that Basara is going to have two younger stepsisters, Mio and Maria. The four of them move into a new house (since the girls' mother is away overseas) and Jin is soon called away on business. The girls take advantage and try to force Basara to leave the house using magic. However, this backfires and Basara tells them to leave. He then contacts his father who reveals the girls' true nature to Basara and why he took them in. Having decided to protect them as their older brother, and in spite of their deception, Basara goes after the girls and saves Mio's life. As they live together and bond, Basara slowly falls in love with the girls, particularly Mio and Yuki, whom he considers as his weak spot. Maria has Basara and Mio perform a master–slave magical contract that allows them to know each other's location. But, Maria unexpectedly makes Basara the master and Mio the slave, not the other way around and because Maria used Succubus magic to form the contract, the penalty for a disloyal servant is a strong aphrodisiac effect that can only be relieved by the touch of the master, leading to a strong orgasmic release. He has also entered a pact with Yuki in order to boost their fighting strength.
Mio Naruse (成瀬 澪, Naruse Mio)
Supporting
Jin Tojo (東城 迅, Tojo Jin)
Voiced by: Keiji Fujiwara (Japanese); Kirk Thornton (English)
Jin is Basara's father, and he is also known as the War God. He has two wives - one is a Demon Lord and the other one is an Angel (Nephilim). He knows of and sympathizes with Mio's situation and that is why he decides to protect her. As a foreign correspondent Jin is largely absent from the Tojo home. His strength is so famous that it kept the Demon Lord Wilbert at bay and almost defeated the Demon Lord Leohart.
Yahiro Takigawa (Lars) (滝川 八尋 (ラース), Takigawa Yahiro (Rāsu))
Voiced by: Tomokazu Sugita (Japanese); Ray Chase (English)
A masked Demon sent to spy on Mio who disguises himself as her and Basara's classmate, but after being defeated and nearly killed, he befriends Basara and they form an uneasy alliance. He is capable of creating dolls to take his place and fights using barriers. Mio's foster parents were his caretakers in the orphanage he grew up in, so he agreed to help Basara on the condition he could kill Zolgia himself, to fulfill his wish and avenge his caretakers.
Takashi Hayase (早瀬 高志, Hayase Takashi)
Voiced by: Go Inoue (Japanese); Todd Haberkorn (English)
A member of the Hero Tribe who wields the cursed spear, Byakko. He is Basara's childhood friend, but has resented him since the incident five years ago. He strongly believes that Basara has forgotten the incident and that any who side with a demon needs to be killed.
Chisato Hasegawa (長谷川 千里, Hasegawa Chisato)
Voiced by: Yuu Asakawa (Japanese); Wendee Lee (English)
The school nurse at Hijirigasaka Academy. She is aware of the supernatural things happening around the students and tends to give Basara advice. A wise and caring person, it is revealed that she was Basara's mother's best friend, and they were close enough to be sisters in all but blood. After Basara's mother dies, Hasegawa dedicates her life to protecting Basara. It is also revealed that she is not human but in fact a god, hinting that Basara's mother was one as well, therefore making him a demigod. She later falls in love with Basara and enters into a secret relationship with him. At the end of the series, she marries Basara along with the rest of his harem and she becomes pregnant with Basara's child.
Media
Light novels
The first light novel volume was published on September 29, 2012, under Kadokawa Shoten's Kadokawa Sneaker Bunko imprint. The thirteenth and last volume has been published on March 31, 2021.
Manga
A manga adaptation with art by Kashiwa Miyako began serialization in Kadokawa Shoten's shōnen manga magazine Shōnen Ace in the July 2013 issue, released on May 25, 2013. A second manga adaptation, titled Shinmai Maō no Testament: Arashi! (新妹魔王の契約者・嵐！), focusing on the antics of Maria with art by Fumihiro Kiso, began serialization in Hakusensha's seinen manga magazine Young Animal Arashi on February 7, 2014. Both series have been licensed for publication in North America by Seven Seas Entertainment.
Anime
An anime television adaptation premiered on January 7, 2015. The opening theme is "Blade of Hope" by sweet ARMS and the ending theme is "Still Sis" by Kaori Sadohara. A second season titled The Testament of Sister New Devil BURST premiered on October 9, 2015. Crunchyroll streamed the series, with Funimation handling the home video release. Anime Limited released the series in the UK.
China ban
On June 12, 2015, the Chinese Ministry of Culture listed The Testament of Sister New Devil among 38 anime and manga titles banned in China.