Ken and Yukina achieved a great victory; they are the only ones in the world who were able to defeat a geoframe of Efidolg, even if Hedo took his own life rather than allow himself to be captured. But it’s far worse than that: Yukina is simply done.
She’s gone along up to this point, but she never truly signed up for this, and she just can’t get into the headspace required to take more life, especially when the so-called “demons” have human form. She retreats into her room; into her dreams; into her past, when she was berated by peers for being the daughter of a presumed madman.
His “lies” made her a liar. She’s always resented this, and her mother was never present enough, either emotionally or physically, to do much about it. So it’s stewed. That Dad turned out to be right doesn’t change the fact she carries scars, even if they’re not the kind that show, like Ken’s (whose bashfulness with “virtually naked” girls during a free swim was another nice touch. Dude is simply not used to women.)
It’s not that she takes a particular moral stance against fighting the enemy; she simply feels deeply in her bones that she’s not the girl for the job. Tom doesn’t help matters by calling her worthless. At school, Yukina feels lost, and she can’t accept the adoration and gratitude of most of her classmates, because some believe she did nothing to save Akagi and Kaya from being killed (their fates remain a mystery).
Sophie, for her part, tries to make an appeal to Yukina’s inner bushido, but to no avail. Yukina doesn’t want to be the person with the fate of the world on her shoulders. It’s just too BIG. Why can’t she just go to the supermarket after work and buy ingredients for dinner?
When Ken finally tries to assure her he doesn’t think she’s just a tool, and then plots out his post-revenge course as leading to his eventual reunion with the princess (i.e. death or suicide), Yukina’s refusal to ride with him intensifies. She doesn’t want any blood on her hands.
She also believes the demons aren’t demons, after meeting one and seeing an ordinary human. We’re finally allowed inside the orbiting Efidolg mothership, where a small council of pilots like Hedo reach the consensus that their plans cannot continue as long as Glongur walks the Earth; it and its pilot must be destroyed.
These spacefaring warriors seem so very far away from Yukina’s simple life, but at this point I just don’t see her staying out of the fighting. Even if her mother won’t force her, something will surely come up to convince Yukina, like her male Eva counterpart Ikari Shinji, to jump into that cockpit once more.
Despite Yukina’s multiple (and reasonable, considering the life she’s led thus far) reservations, and the fact this week ends with her running away from home after her mother slapped her for being presumptuous about her late father, this only seems like delaying the inevitable: Yukina and Ken will keep fighting Efidolg, because no one else can, and because those Yukina loves and cares about will be in danger if she doesn’t.
There’s also, like, a million episodes left. Way too early for our heroine to throw in the towel…but probably not the last time she’ll waver, either.