From the moment that she bound Zia, Ristella had paid close attention to her reaction.
She even purposely tightened the chains, deliberately inflicting great pain on the young lady whose life and death were in her hands.
But from the beginning until now, Zia's face showed no reaction—no pain, no fear, no nothing. Only indifference.
Ristella could also sense the bodily functions of anyone wrapped by her chains, including their heartbeat.
This meant that, if Zia had been merely acting to look calm on the surface, she'd be able to tell if the teenager actually felt nervous inside.
However, the young lady's heart was beating normally, and despite the pain she was feeling, she wasn't showing any reaction, both inside and out, which puzzled Ristella.
"You must be thinking that I won't really kill you, huh?" Ristella asked, ignoring the two succubus princesses who were trying to free Zia from her chains using their bare hands.