The Testament of Sister New Devil

After the struggle for supremacy involving the entire demon world settlled down, Basara and the girls have regained their peaceful everyday life. One day that starts with Mio's "Full of Wrong Bathroom Soap" play, they go to an indoor pool on Maria's recommendation. However, Mio activates her curse of aphrodisiac by Basara's accidental action! For Mio who is writhing painfully, Basara decides to take an action in the pool...!? Meahwhile, Yuki and Kurumi receive an order from the hero village that is making a threatening move. Basara and the girls' exciting vacation begins in a short holiday!