I have found two previous similar questions (and tons way off), see below, but mine is distinct.
My question is about the atonal music played during Rize and Kaneki's dialogue and his torture in season 1 episode 12 from roughly 0:00–13:13, not "Rize's Melody" / Original Sorrow", which starts at 14:00 after 40 seconds without music. What's this atonal music called? Is it released or named?
It evidently isn't "Unravel", and it does not feature strings as much as "Die Verwandlung". I have gone through the two OST disks and not found it.