新妹魔王の契約者 BURST 東城刃更の至極平和な日常

An OVA that was bundled with the seventh volume of the Shinmai Maou no Testament manga. What’s the best way to celebrate a birthday? Well, to the succubus Maria, there’s only one thing to do—get Mio and Basara to hook up! Using the guise of Mio’s birthday, and a lust spell, she’s determined to have the perfect setup for a sexy celebration. (Source: Funimation)