Rakkasen

"Evil began in a time before recorded history, when Shinigami made themselves into kings... and gods... using the powers of the darkness. The weak-minded have ever been ready to obey one who wields great power. Those who learned the powers of the darkness were quick to exploit this weakness—to make war. Again and again the darkness has surged forth, like a storm... devouring whole worlds and entire lives. Those who mastered the darkness became law. They unleashed destruction, for no other reason for selfish gain. They despoiled nations... destroyed whole civilizations. Some of them, I am ashamed to say, were Seijin."

- Junsui Kirei

Rakkasen (倒れたセージ, "fallen sage"; literally falling hermit) is a Seijin that had fallen under the influence of their dark emotions; feelings such as anger, hatred, regret, and pain. They rely on the darkness and evil applications of spiritual power; involving personal gain, killing, influencing others, and taking control of the innocent. The Rakkasen believed that conflict was the only true test of one's ability, and so emphasized its importance. It was their belief that conflict challenged both individuals and civilizations, and so forced them to grow and evolve. They believed that the avoidance of conflict–like the pacifist teachings of the Seijin–resulted in stagnation and decline. The cornerstone of a Rakkasen's power was emotion. While the Seijin taught that fear, anger, and pain were negative emotions to be overcome, the Rakkasen believed that these strong emotions were natural, and aided individuals in their survival. By harnessing their emotions rather than suppressing them, the Rakkasen believed they could achieve true power. This belief was in stark contrast to that of the Seijin's, who strived to place themselves beyond such base emotions. They believed strongly that the worthy could control their emotions and use them, while the weak were ruled by them.

Behind the Scenes
Staying true to the Star Wars influence of the Seijin, the Rakkasen are based off the Sith, who are the extreme opposites to the Jedi, which the Seijin find their influence from.