Kaori crosses swords with Acqua, whose birth name we learn to be William Orville, a former mercenary for the Anglicans but moved to the Roman Orthodox church. We also learn that Kaori, on her own, is absolutely no match for him.
His attacks have her flat on her back and spread eagle across vasts fields of rubble and debris, though to her credit she never stops getting up and dusting herself off, a resoluteness he admires even if he’s quite certain there’s nothing she or anyone else can do to keep him away from Touma.
As for Touma, he’s limping towards the battle when Misaka encounters him, and insists that he allow her to help. That might well have made the fight an easy one for him, but he declines the offer, and while she’s not happy about not being able to fight, she can understand there’s significance in him going it alone.
That’s ironic, since Kaori, who left the Amakusa church in part to protect her comrades, categorically can not stand alone and survive against Acqua; he’s just too goddamn talented and powerful, and the more beat-up she gets, the more his confidence in victory soars.
But he didn’t count on Kaori calling to Amakusa to jump down to the level of the battle and combine their powers to help her. Itsuwa was just getting done talking about how she and her group’s fighting was child’s play compared to the scale of a saint-on-saint battle (and it was), but Kaori doesn’t need them to defeat Acqua, she just needs a little help.
She gets it, and Acqua is sufficiently distracted in trying to bring the hammer down on all of them that he completely misses Touma slipping him below him, in the direct path of the attack, which Imagine Breaker nullifies in a very satisfying moment.
In Acqua’s moment of vulnerability, Itsuwa comes back at him with Saint Breakout and this time it works. The multi-pronged attack on him actually reminded me of the Avengers in one of their attempts to use teamwork and elaborate tactics to bring Thanos down on Titan. They failed, but Touma, Itsuwa, Kanzaki and Amakusa succeed: Acqua is defeated.
After a brief flashback to when William Orville left England, Touma wakes up back in the hospital, under the gentle ministrations of Itsuwa. The two get a little too close for Index’s comfort, especially considering she was by his bid longer.
Kanzaki wants to thanks Touma for his help, but is a bit squirrelly about it until Tsuchimikado breaks out a “fallen angel maid” outfit for her to wear. Unfortunately we never get to see it in all its glory, but it certainly makes an impression on Index, Itsuwa, and Touma! Glad to see the lighter side of Index closely follow the stern and serious climactic battle.
From there we’re shown the next threats to Academy City in Fiamma of the Right, apparently the leader of the Right Hand of God. While Acqua took out a pillar in the Vatican, the damage Fiamma causes attacking the Roman Pope cracks the dome like an egg. That is not going to buff out!
After Fiamma takes off with Index as his target, the Pope orders the fourth member of RHoG, the pierced-up Vento of the Front, to go after Fiamma. Of course, Vento doesn’t take orders from the Pope, but she’s going anyway.
Finally, we also get a glimpse of Mr. Academy City himself, Al Crowley, upside down in his office-cocoon thingy telling his computers to do various things relating to Imagine Breaker. Looks like we’ll have plenty of material to work through to fill the remaining sixteen weeks.