Legend of Qin Ruo
Qin Ruo, the alchemist of the Profound Cloud Continent, was attacked by several opponents when he was about to become one with the pill. His soul managed to escape and possessed the body of the third son of the head of the ancient Qin Clan in Wuzhen's six major families named Qin Ruo. As the son of a big Huaxia family who couldn't cultivate, he was abandoned so as not to bring shame on them. With this body, Qin Ruo would strive to regain his former glory. Anyone on his way would only be a stepping stone.
Once Upon A Time [XLI]
Seeing this, Qin Ruo sighed and thought, maybe the knowledge about alchemy and human body refinement in his mind was transferred to his mind by his mother using magic when she was dying. No wonder he somehow knows so much.
Qin Ruo thought again, at that time, his mother had already seen that the purpose of alchemy organizations such as Blood Moon, Death God and Blood Rose was to obtain controllable Klass. But what is Klaas? Why do they have to control Klaas?
Qin Ruo suddenly remembered that he had seen the name Klaas on Duanmu Ruiguang's computer. Moreover, Duanmu Ruiguang seemed to hesitate several times when the android he made escaped, saying that the android might be "that kind of thing". Now it seems that Duanmu Ruiguang did not speak out, but avoided saying "that kind of thing" referring to "Klass".
Perhaps when androids mutated into "things" with frightening powers and abilities, the alchemy world called them "Klass"?