- Type: TV
- Studio: Production IMS
- Publish Date 2015-01-08
- Status: Completed
- Genre: Action Animation Ecchi Fantasy Romance
- Scores: 2.53 by 4,405 reviews
- Duration: 23 min
- Views: 486
The Testament of Sister New Devil
Basara Toujou learns the hard way that running into your new stepsister in the restroom is not the best way to make an impression. He is forced to welcome the Naruse sisters, busty redhead Mio and petite silver-haired Maria, into his household when his father unexpectedly brings home two lovely females and introduces them as his new siblings. Basara is forced to come out as a former member of a clan of "Heroes," sworn opponents of the demons, when these two seemingly normal girls—Mio, the previous Demon Lord's sole daughter, and Maria, her devoted succubus servant—reveal themselves to be demons. Basara, who has been taking care of his new sisters, decides to use his powers to protect them instead. He also enters into a master-servant relationship with Mio to keep an eye on her. Basara has to go above and beyond to defend his new family members because the Heroes are constantly watching him and there is a continual danger from hostile demons. Additionally, the protector himself is concealing a sinister secret that continues to plague him now.