You've got to be kidding me. I thought for sure all the answers were going to come and then it ended with a cockblock like that.
I feel like the answer must be obvious, but still, I don't know. I mean, I have my theories, but I feel like they aren't right.
My assumption, at least, are that Shannon/Kanon/Beatrice are all the same person. What Battler was supposed to remember was that talk he had with Shannon, detailing his ideal girl. It's all a case of some strange multi-personality disorder: Shannon/Kanon/Beatrice are all facets of one person, created to be with three different people (George/Jessica/Battler).
...Or something like that. It would probably explain some things about the past games, even though I still don't fully comprehend how it is supposed to work.
I'm pretty sure Natsuhi's cliff incident and Rosa's cliff incident are related because iirc they were both 19 years ago. I'm not sure in what way though. At the very least, the baby isn't supposed to be Battler, but Shannon/Kanon/Beatrice. And maybe the baby's mother was the other Beatrice, the one in the forest?
I don't get the logistics of the closed room though, I mean even in the hypothetical that Kanon/Shannon/Beatrice are all the same person I can't explain how Kanon entered the room yet still left it. Honestly the entire chapter I thought maybe Erika helped him, or that someone had been in the room the entire time with Battler, even though I couldn't explain why. So in the end the answer was never in my reach.
All in all I'm probably misinterpreting something, and am completely wrong. I just don't know anymore. I feel like there were a lot of hints this chapter
(am I missing something or does this not imply Rosa was one of the culprits) but I don't think any hints can help me now, all these theories have eaten away at my mind. I'm never going to get the answer unless it's just plainly stated.
Erika was fun this chapter though. The voice acting in this is so goddamn good, I love it with they go full crazy taunting mode. Beatrice is the king of this with the almost yakuza-like tone she goes sometimes, but
Erika is also pretty great too with her English.