---
title: "The Testament of Sister New Devil"
year: 2015
canonical_url: "https://www.archytele.com/show/the-testament-of-sister-new-devil-2015"
media_type: "tv"
tmdb_id: 64163
imdb_id: "tt4219258"
status: "Ended"
seasons_count: 2
episodes_count: 22
runtime_minutes: 24
community_rating: 7.9
vote_count: 362
content_rating: "TV-MA"
---

# The Testament of Sister New Devil (2015) — Television & Cinema Intelligence Dossier

> **Archytele Living Vault Canonical Record**: https://www.archytele.com/show/the-testament-of-sister-new-devil-2015

## Executive Summary & Cultural Positioning

The Testament of Sister New Devil is an anime television series that originally aired from 2015 to 2016. The story follows a high school student named Toujou Basara whose father suddenly remarries and departs for an overseas trip. Basara is left in the care of two new stepsisters, Mio and Maria. Unbeknownst to Basara, his new siblings are actually a Demon Lord and a succubus. Following an accidental reverse contract, Basara becomes Mio’s master instead of falling into a life of servitude. As he navigates his new living situation, Basara frequently finds himself in various ecchi scenarios. The plot intensifies as Mio’s life is placed in danger due to persistent threats from both demons and heroes who are pursuing her. The series is available for streaming through platforms such as Crunchyroll and JustWatch. The production credits for the series, including information regarding directors, writers, and the cast of actors and actresses, are documented in industry databases.

## The Hook & The Verdict

**The Hook**: "A high schooler discovers his new step-sisters are supernatural beings and becomes their accidental master."

### Why Watch
- features supernatural character dynamics
- includes comedic hijinks

### Caveats & Content Note
- contains frequent suggestive situations
- Tone & Suitability: This series contains mature, suggestive themes and ecchi content unsuitable for younger viewers.

**Micro-Themes & Vibe Matrix**: supernatural, ecchi, comedic, action-oriented

## Streaming Availability Matrix

| Region | Stream (Subscription) | Free / Ads | Rent / Buy |
| :--- | :--- | :--- | :--- |
| **United States (US)** | Crunchyroll, Crunchyroll Amazon Channel | None | Apple TV Store |
| **United Kingdom (GB)** | Crunchyroll, Crunchyroll Amazon Channel | None | Apple TV Store |
| **Canada (CA)** | Crunchyroll Amazon Channel, Crunchyroll | None | Apple TV Store |

## Season Architecture & Lore Primers

### Season 1 (12 Episodes)
The Testament of Sister New Devil is an animated television series that debuted in 2015. The story centers on Toujou Basara, a high school student whose life changes abruptly when his father remarries and subsequently leaves the country. Basara is left in the care of his two new stepsisters, Mio and Maria. Unbeknownst to Basara, his new sisters are not ordinary humans; Mio is the new Demon Lord, and Maria is a succubus. 

The narrative follows the complications that arise when Basara is nearly forced into a life of servitude. Instead, he accidentally forms a reverse contract that establishes him as Mio's master. This dynamic leads to a series of ecchi situations for Basara as he navigates his new living arrangement. The plot further develops as Mio becomes a target for various demons and heroes, placing her life in constant danger. The series is categorized under the genres of animation, action and adventure, comedy, and science fiction and fantasy. It is rated TV-MA.

## Filler vs. Essential Episode Classifier

- **Total Tracked Episodes**: 22
- **Crucial Mytharc Episodes**: 4 (18%)
- **Character Core Episodes**: 18 (82%)
- **Side Quest / Filler Episodes**: 0 (0%)

## Key Cast Continuity

- **Tomokazu Sugita** as *Yahiro Takigawa (voice)*
- **Yuichi Nakamura** as *Basara Tojo (voice)*
- **Ayaka Asai** as *Mio Naruse (voice)*
- **Kaori Fukuhara** as *Maria Naruse (voice)*
- **Sarah Emi Bridcutt** as *Yuki Nonaka (voice)*
- **Keiji Fujiwara** as *Jin Tojo (voice)*
- **Seiko Yoshida** as *Zest (voice)*
- **Yuu Asakawa** as *Chisato Hasegawa (voice)*
- **Iori Nomizu** as *Kurumi Nonaka (voice)*
- **Masaaki Itatori** as *Kraus (voice)*

## Canonical Frequently Asked Questions

### Q: What is the premise of the series?
Basara Toujou finds himself living with two step-sisters who are actually a Demon Lord and a succubus.

### Q: What happens to Basara?
He accidentally forms a reverse contract that makes him the master of his step-sister, Mio.

### Q: Is there conflict in the show?
Yes, Mio is pursued by both demons and heroes, placing her life in constant danger.

### Q: What is the tone of the show?
The series balances supernatural action with frequent ecchi situations.

### Q: Does the father play a role?
The father leaves for overseas shortly after remarrying, leaving Basara alone with his new sisters.

## Grounded Source Citations

- [Testament (band) - Wikipedia](https://en.wikipedia.org/wiki/Testament_(band))
- [The Testament of Sister New Devil (TV Series 2015-2016) - IMDb](https://www.imdb.com/title/tt4219258/fullcredits/cast)
- [TestamentLegions.com – Testament Official Site](https://www.testamentlegions.com/site/)
- [Watch The Testament of Sister New Devil - Crunchyroll](https://www.crunchyroll.com/series/G67570P3R/the-testament-of-sister-new-devil)
- [TESTAMENT Definition & Meaning - Merriam-Webster](https://www.merriam-webster.com/dictionary/testament)
- [The Testament of Sister New Devil - streaming online - JustWatch](https://www.justwatch.com/us/tv-show/the-testament-of-sister-new-devil)

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*Generated by Archytele Open Intelligence Systems. Data verified against TMDB and JustWatch APIs.*