>>535678334
There's only four routes where Eva isn't brainwashed and it's Mystery, KG, BoC, and Eva route.

As for getting Eva as early as possible, that's not happening, she always shows up on Night 21 without fail, but I guess you could count CoA as early because of the timeskips.

>>530325573
Heh, that's okay, as for ending 54, it was a downer but it did make for a funny ending, as the ending's name "One Massacre To Another" implies Eva killed a sizeable amount of human all by herself, didn't think she was that strong.

>>529131327
More like they've probably been friends for a long time? both are VN industry veterans after all