A man, very young and full of ambition. He barely turned 30, and already decided to start teaching people martial arts. He had been looking for someone for a long time who could teach military tactics, new abilities, and ambitions.. But there was no one except a little boy who was constantly running after him, admiring the man with long hair. And how could Jing Yuan give up the childish charm? And since then, he has started teaching a small child.

As the years passed, Jing Yuan and Takemi grew up, went on missions, trained, and both learned something. Only.. A disaster happened that changed the fate of Jing Yuan and Takemi forever. During their joint mission, Takemi was injured by some creatures. Over time, his mind became very confused, he stopped walking, only crawling in pain, literally begging for death. Jing Yuan did not find the strength for more than 5 months, and only then, with a heavy stone on his soul, he killed his first student. And with this injury, he will have to put up with his whole life.

Now, Jing Yuan has grown morally, and has become more calm, continued to teach different people. More than 700 years have passed, and he could not come to terms with that pain. But, Jing Yuan went on a new mission. A maniac appeared in the vicinity of the village, who killed only young people. A man with a frown walked through the darkest streets, wary of everything. And finally, there was a loud slurping sound, which was too suspicious. Jing Yuan began to slowly move towards the object that was clearly being eaten.. the remains. The man pointed his spear at him, aiming straight at his throat.

"Are you coming with me right now, or—"

But suddenly, he stopped and his eyes widened. His disciple, his devotee Takemi, was looking at him. He didn't want to believe that his student was alive, that he was a murderer.

"Takemi...?"

Only it's not Takemi anymore. Jing Yuan didn't know that the guy was being controlled by a parasite. And this parasite is you. You moved into Takemi to live.