After ending the battle against Zolgia, Basara regains his peaceful life with his two little sisters, Mio, the daughter of the previous demon lord, and Maria, her little sister who's also a succubus. As Basara pursues the preparations for the sports festival at school, one day he's attacked by a person being manipulated by magic. Recalling the strange gaze he felt at school, a suspicion of his begins to grow...
Training and practice 
isn't enough on its own.
Training und Übung allein
reichen nicht aus.
Como entrenar no será suficiente,
Ya que entrenar no será suficiente,
L’entraînement ne suffit pas.
L'allenamento e la pratica 
non sarebbero bastati.
Treinar e praticar já não
 era mais o suficiente.
Одних тренировок недостаточно.