Summer break is coming up fast for Hyodo Issei, but all his plans are put on hold when he finds out he is to accompany Rias for her visit back home to the underworld! A new adventure is about to begin and all the while Koneko is not acting herself.

Sairaorg has finally risen up to the stage and Kiba, Xenovia, and Rossweisse team up against him. The battle is swift and brutal and Issei is finally reaching his bursting point. Will he be able to channel his feelings? Or will resentment take over?