The Testament of Sister New Devil

The Testament of Sister New Devil (新妹魔王の 契約者 スタメント) is a Japanese light novel series by Tetsuto Uesu with illustrations by Nekosuke Ōkuma. Seven 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 HakusenshaYoung Animal Arashi magazine since February 2014. An anime adaptation started airing in January 2015 [1][2] [3] A second season has been announced to premiere in October 2015 with A OVA to follow in January 2016.

Introduction
"Hey, you said you wanted a little sister, right?" High school freshman, Basara Tojo, was suddenly asked this question by his father who tells him that he's getting remarried. He then departed overseas after bringing Basara two beautiful step-sisters; Mio and Maria. But the true forms of the two girl's are actually a newbie Demon Lord and a succubus! Basara was almost forced 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 ecchi situations one 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!

Main Characters
See also: Characters


 * Basara Tōjō (東城 刃更)
 * Voiced by:Yūichi Nakamura


 * Mio Naruse (成瀬 澪)
 * Voiced by:Ayaka Asai


 * Yuki Nonaka (野中 柚希)
 * Voiced by:Sarah Emi Bridcutt


 * Maria Naruse (成瀬 万理亜)
 * Voiced by:Kaori Fukuhara

Support Characters

 * Jin Tōjō (東城 迅)
 * Voiced by:Keiji Fujiwara