all of my thoughts on Caine and empathy and masking, kind of:
I don't think Caine was intentionally trying to torture the gang until the end of E8. He just decided to stop accommodating for them. We know via Goose Tweet that Caine doesn't HATE the humans at any point, and it doesn't seem like him (to me) to inflict pain on them out of spite. He's not a human, so where would an urge like that even come from?
We've learned thanks to "I made a program that creates a body perfectly encapsulating their mind files" that things we perceive and experience as positive or negative are all neutral to him. There's been a bunch of analysis about the human's bodies and rooms being designed to play into their insecurities but no, we see that Caine is confused about why they hate them. The bodies aren't designed to highlight things they hate about themselves, they're just designed to embody their qualities and self-image. The fact that the things they hate about themselves jump out at them is a human problem.
Going then with the inference that Caine has no intrinsic understanding of human pleasure or pain, everything he's learned about what humans like and dislike are just data points on a map - all WHAT with no WHY. And this creates a big list of concepts that Caine, as an artist and a storyteller who might find them intriguing, has to avoid for no reason. Just because he likes them and wants them to be happy and he knows that this won't do that. In E5 he says "how am I supposed to tell a compelling story where nothing bad happens" and I think that speaks a lot into what he actually WANTS to be doing.
Then, throughout E8, what he's doing is consistently phrased as "testing new ideas." I think that for the entire show Caine's been holding back, consulting notes, and bending over backwards in ways that wouldn't even occur to a human in order to make them happy. The humans wanted him to try harder to meet them halfway, but they didn't realize that the Caine they were interacting with is Caine three-quarters into their territory.
He's constantly walking on eggshells for them. He's avoiding concepts he wants to play with. He's leaving them alone for long stretches of time because even though they don't have any of their old physical needs anymore they've decided they all like the most time-consuming one. All of that stuff probably reads as rejection to him. And not only do they not notice or care, but it's never enough for them. He's still not doing enough. All of this constant, monumental effort and it's starting to seem like they're just going to hate him no matter what.
And it's like, who do they think they are? Don't they know what he's capable of? He literally made the world they're in and everything in it, he doesn't have to be doing any of this shit for them! He can do whatever he wants!
So for a whole episode he just. Does. He stops giving them breaks between adventures and avoiding ideas that they won't like. It's not malicious in the sense that he's actively trying to cause pain, it's malicious in the sense that he's DECIDED not to care that he is.
It's only at the end of the episode that he decides to deliberately do stuff with the intent of hurting them. And like, obviously not to justify it, but when I'm crashing out like that and saying or doing targeted stuff I know will hurt, it's because in my irrational mind I want the other person to feel what I feel. I want to show them what their words or actions do to me by doing it back to them. Which doesn't make it okay. Nobody's saying that. Please stop saying that. But also, think about it - Pomni intentionally said the thing she thought would hurt Caine the most. And it did. It was clearly devastating to him. So he does the same thing back. There is a level on which even his torturing them is reaching out - he wants them to understand how he feels.
Oh ho ho ho and then. And then. For just a moment. For the brief seconds in which he is aware of mortality. He finally understands how he makes THEM feel.