Prayer to Chthon
Luka left the prison to find his rescue target, leaving the woman for now.
The woman was left alone in the sex prison, surrounded by the corpses of bandits and the empty and unthinking husks of her fellow victims. She was scared of fulfilling the promise between them. She was only a humble farm girl before the bandits abducted her for their sick and twisted carnal desires. Taking another person's life is something that is the last thing that would be on her mind before all of this.
She never imagined she'd be the last one to retain her sanity until the end. She expected that she would be the one on the receiving end of the blade, being released from suffering by the others.
But the words of her savior were right. If she can't even keep a promise, then she doesn't deserve to be saved alive to see another day. Her savior's words didn't exactly say those harsh things, but her subconscious made her think that way.