Ciel Sensei

In a parallel world, there was a genius in creating weapons of mass destruction. One day his house was attacked by his superiors in fear that someday he would betray them. The man lived, however, his entire family was killed. He then decided to sought for revenge and use his weapons to kill his enemies. However, this story is irrelevant because I don't live in that world. My name is CielSensei. Nice to meet you. XD

"Sometimes, the story of the NPC is better than the hero. 
The hero has a predetermined route; go on an adventure, get strong, kill the boss.
The NPC, however, is unknown. That's why it's interesting."