Cassandra / Cullen
From what I have seen thus far, Dorian is furious. I would not count on him for a cool head. Not that I can blame him. No one deserves to have magic twist their selves and lives up into something else like that.
Which is not to say I will be advocating for execution or Tranquility or anything of that nature. There must be some assurance that this will not happen again, however.