A Certain Magical Index Vol. 26 (manga)

Desc:  Itsuwa and the Amakusa Church struggle to defend Touma from Acqua of the Back, but it seems like even their combined strength won’t be enough…until their own ace in the hole arrives! Kaori Kanzaki returns to aid her comrades in their hour of need, setting the stage for a deadly duel. Will there be anything left of Academy City after the two saints clash?