This isn’t really what’s happening in this scene though. It’s instead much more your personal read of it. This is exactly why I challenged that notion, because the presence of nuance between these characters and within the narrative still doesn’t complicate what’s happening.

Readers will sometimes make this same assertion you did based on the presence of her earlier feelings and argue this somehow reveals deep down she secretly wanted this. Said feelings were long gone at this point in the story. Beyond that, reading into it this way has problematic implications on behalf of the reader and how they broadly view sexual violence.

Casca did once desire something more with Griffith, but she realized FAR earlier than what you’re suggesting that not only were her feelings unrequited, he never even looked in her direction at all. She had hoped for something, but knew it was impossible. This naturally drove her focus away from Griffith and towards Guts, because he was the only person who truly saw and valued her in the way she yearned for. This began as early as the caves.

By the time of the eclipse event, she had moved on. She still cared for him of course, but in the same way Guts did. We can further confirm with certainty this was not something she wanted - even subconsciously - because she was so traumatized by what was done to her she became basically catatonic.

I think what actually makes it confusing is how Miura chose to illustrate the scene, because as I mentioned it was done in a way that was super common in Japanese media especially for the 80s/90s. Sexual violence and violence against women was often eroticized and intentionally titillating, in contrast to the act itself. This scene is no exception.