It feels like I have to give up watching this anime after episode 8 but I must wait til the finale to decide whether is normal ending or yuri ending. Episode 8 will be pre-apocalyptic scenario after the statement describes that if the injection of Armed virus into a clone was succeed into the future, there'd be no more Liberators and Exstars.
That doesn't preclude of girls/women being naturally infected, it just means that they can make an army for themselves and not worry in finding suitable Liberators/Ecstas.
Hell, her new form can be seen as being a showing of the love she feels for Mirei.
I guess we see things differently, after all, why did she power up? Because of Akira/Hilholde :P Furthering the 'fated for each other' cause she didn't respond that way to Mirei.
Mirei may have not been a willing participant in the experiments, I don't know why people assume that, the shame she feels of her form kind of supports it. And before you say, 'well in the flashback she seemed pretty obedient', that just means that they could've 'beaten' her into submission. As for Momoka it's kind of clear she's gonna be the baddie when she 'transfers' or at least based on what they showed of her.