While I appreciate the cool makeshift torture I just can't help but feel her revenge is shoehorned into the story too abruptly, something like, "Hey, look! It's still a revenge manga if she has a grudge on this sub-boss, yeah?"
I can understand exploring the roster and strengthening their plot relevance, but I do hope we'll get more clues on Kyou soon after this. He's getting kind of forgotten in the backburner, I swear.