When Yura/Kanzaki finds Aico, she’s already willing to forgive all the lies he’s told to that point, because she exists in part because of those many lies. She’s also as ready as ever to sacrifice herself to save her mother, brother, and the “real” Aiko, even though that Aiko has already offered to do the same. For his part, Kanzaki is hesitant in the moment to let Aico go through with it, even though, as she says, that’s how the Burst will end.
In that moment of hesitation, Dr. Isazu hooks himself up to some kind of interface we’ve never seen before which allows him to connect to and manipulate the same Matter as his unconscious daughter.
Isazu uses the human-form Matter to restrain Aico and Kanzaki and a rather lengthy argument with the latter ensues, densely packed with a whole mess of technobabble about networks and cell assemblers. Suffice it to say, Isazu wants his daughter back, and is willing to sacrifice both Aikos to do so; Burst be damned.
Isazu gets increasingly frustrated with Kanzaki’s apparently boundless, “god-like” genius, but is unable to kill him, because Kazuki swoops in just in time to free Kanzaki and Aico from their bonds. A torrid chase ensues, and the real Aiko succeeds in suppressing the purple Matter with her Red long enough for the trio to get to shelter…only it’s not the shelter, but some kind of storeroom.
There, Kanzaki gathers materials for a makeshift explosion to blast their way out of their dead end and continue to Primary Point, but Kazuki doesn’t want Aico to go…because he’s fallen in love with her, plus when the matter attacked his arm he saw her memories. Aico tells him she’s flattered by his confession, but if he truly loves her as he says, he’ll let her save her family, which she can only do by reuniting Aiko’s body and brain.
Back outside the area, the JSDF is poised to start their bombardment of the entire facility, but they’re foiled at the last second when Nanbara lifts the blockade on the Area and sends in wave after wave of civilian Divers. The generals must hold their fire, and Nanbara is summarily fired by her superior, though her assistant Hori remains on the job for the time being, likely by design.
Nanbara gave up everything to save the Matter that will keep her country at the forefront of science from being annihilated by that same country’s military.
Now we’ll see if her sacrifice, and those of Shinoyama and many others, will be validated, as Kanzaki finally gets Aico to Primary Point, where the Burst and Aico’s existence began. The other Divers are holding their own, led by Sagami and Shiraishi and now convinced that what they’re doing has a crucial and noble purpose.
After many trials, lies, revealed secrets, and yes, one very lame confession, Aico has reached her destination, and it’s where she herself has chosen to come. Now let’s see if she and Kanzaki can end the Burst, save her family, wake Yuzuha up, and maybe, just maybe, save Aiko as well.