As annoying as this arc has been, the more I think about it, the more logical it all seems. I mean, they're basically in a shitty kid's book that's been corrupted by an amasogi, right? That'd kinda account for why it's so stupidly cliche while also being really perverse. I can't count the number of stories I've read aimed at younger readers that have a character that does a bunch of messed up shit only to be shown to be a secretly good person who did those things for someone close to them; it's like some kind of Saturday morning cartoon's moral of the week with how often it shows up.
It also makes me wonder about the girl they're there to save, who's obviously the two-faced beast girl; in the outside world, it's been three years, but how long has it been in the book's world? Is there a time dilation in the book? Does the story loop back to the beginning after the epilogue? If so, I have to wonder if she's still even really herself or if she's been almost fully subsumed by the character she's been forced into.