Koneko's sister Kuroka has appeared to take her sister away from Rias Gremory. Issei and Rias chase after her to stop that from happening. At the same time, a figure who objects to these alliances between mythologies appears at the great gathering.
Casts:
Yuki Kaji, Yoko Hikasa, Azumi Asakura, Shizuka Itoh, Ayana Taketatsu, Fumihiko Tachiki, Saori Seto, Risa Taneda