Kamichama Karin Chu Vol 7

From the Del Rey Manga edition

Rika has succeeded in awakening the evil Professor Kirihiko Karasuma, and the two escape to the future. Karin and the others follow, but Kazune can't fight without his ring, and the Professor is too powerful! It's time for the final showdown - can Karin and friends really save their future?

Source: Anime News Network Encyclopedia