Mori is the main antagonist of the series with a resemblance to Frankenstein's monster. He is Tsukino Mori's husband and Kurei's adoptive father. He trained Kurei to suppress his emotions and become his killing machine. He is extremely rich, and longs for eternal life so he can fully enjoy all his money. He sets up advanced cloning labs and wants to get his hands on Yanagi because he believes that her healing powers can help him achieve eternal life. In the manga, he eventually finds out about and obtains the madōgu Tendō Jigoku, which is said to be able to grant its wielder eternal life.
Kōran is the one of the most sadistic and bloodthirsty characters of the series. He desires countless things such as money and power. He is obsessed with becoming immortal.
He is psychopathic, depraved, greedy, and feels no guilt whatsoever for his wicked and despicable deeds, willing to do anything and everything to get what he wants, whether through bribery, kidnapping, torture, or outright killing.
Kōran is extremely wealthy and has a lot of connections, being able to have acquired a large number of madōgu for his and Kurei's soldiers. He has been able to have several advanced cloning labs made.
After fusing with Tendō Jigoku, he attains a vast array of powers:
- Regeneration and Immortality: His body can regenerate limbs at a high speed and can survive having his head cut off and having a big hole through his stomach.
- Enhanced Strength and Speed: He is extremely strong, surpassing Domon in this regard and also exceeding Fuko's speed.
- Body Manipulation: He can manipulate his body in unique ways such as growing spikes or extending limbs.
- Replication: If a part of him is separated into big enough pieces, they can regenerate into mutated copies of him.
- Energy Blasts: He can fire powerful blasts of energy from his mouth, as can his clones.
- Energy Restoration: Using some of these powers take a lot out of him, he can refill his energy stores by eating people (and inheriting their powers/skills in process, as he does with Renge and attempts to do with Yanagi).
- Fire Manipulation: After devouring Renge, he gains the ability to manipulate and be immune to almost any flame