Title: The Testament of Sister New Devil
Japanese: 新妹魔王の契約者〈テスタメント〉
Airing date: 7/1/2015 (TV series, 12 episodes) and 21/12/2014 (premiere screening at Kadokawa Cinema Shinjuku, Tokyo)
OVA release date: 22/6/2015 (unaired episode bundled the eighth light novel volume)
Genres: Action, Ecchi, Fantasy, Romance, Harem
Original creator: Tetsuto Uesu
Original character designer: Nekosuke Ōkuma
Director: Hisashi Saitō
Written by: Takao Yoshioka
Music by: Yasuharu Takanashi
Character designer: Yoshihiro Watanabe
Chief animation directors: Hong Shen (FAI) and Yoshihiro Watanabe
Director of photography: Tsubasa Yokoyama (T2Studio)
Art director: Ryōka Kinoshita (Studio Biho)
Sound director: Tsuyoshi Takahashi
Sound effects by: Tsutomu Ueno and Yasuyuki Konno (Swara Pro)
Special effects by: Tomoki Murakami
Main animators: Kazuya Morimae and Masami Imai
Action animator: Eiji Ishimoto
Art setting by: Saaya Kinjō (Studio Biho)
Color design by: Takao Kanakubo (TripleA)
Monster design by: Shinpei Kobayashi
2D design by: Tomoki Murakami
3D CG by: Tetsuya Watanabe
Planning by: Takeshi Yasuda
Editing by: Yoshiaki Kimura (IMAGICA)
Producer: Chiaki Kurakane
Executive producer: Takeshi Yasuda
Assistant producer: Mari Sakai
Animation producer: Jiyū Ōgi
Music producer: Shunichi Uemura
Sound production by: Eri Itō
Studio: Production IMS
Network: Tokyo MX, SUN, AT-X, GBS, MTV, BS11, TVS, CTC, tvk, TVQ
Opening theme: "Blade of Hope" by sweet ARMS
Ending theme: "Still Sis" by Kaori Sadohara
Main cast: voiced by Yūichi Nakamura
voiced by Ayaka Asai
voiced by Kaori Fukuhara
voiced by Sarah Emi Bridcutt
voiced by Keiji Fujiwara
voiced by Yū Asakawa
"Lars" (ラース) voiced by Tomokazu Sugita
voiced by Iori Nomizu
voiced by Seiko Yoshida
Supporting cast: Takashi Hayase (早瀬 高志) voiced by Gō Inoue
Kyōichi Shiba (斯波 恭一) voiced by Daisuke Hirakawa
Mamoru Sakazaki (坂崎 守) voiced by Kenjirō Tsuda
Zolgear (乙回し呂ヨ丹尺)
Varga (レ丹尺呂丹)
Official website, PVs and CMs: http://anime-shinmaimaou.com/
Synopsis: “Hey, you said you wanted a little sister, right?” First year highschool student, Toujo Basara, was suddenly asked by his father and fell into a state of panic. On top of that, the eccentric father told him he will be getting remarried. He then departed overseas after bringing Basara two beautiful step-sisters. But Mio and Maria’s true forms are actually the newbie Demon Lord and a succubus!? Basara was almost entered into a master and servant contract with Mio, but a “reversed” contract was formed by mistake, and Basara is now the master!? Moreover, Basara is being hit by one ecchi situation after another due to the contract, but Mio’s life is being pursued by other demon tribes and hero tribes! The most powerful contractor’s desire action drama begins!
Necropinion: ep.1 hooked me more than Estetica, well it's the same creator