"I have a question." An Qingyu seemed to have remembered something. "You should exist in the form of a magnetic field now, not a soul. Why can you possess Lin Qiye?"
"In a sense, that wasn't possession. I merely connected my own magnetic field to his brain's magnetic field, simulated some emotional signals, and controlled his actions. I didn't invade his mind," Jiang Er explained.
"So your kind of possession can be used regardless of Mental Power level?"
Jiang Er nodded. "In theory, yes. But the human brain's magnetic field is constantly changing. It fluctuates with different emotions, and if the frequency of those fluctuations exceeds my range of adaptation, I'll be expelled by the magnetic field.
"And the stronger a person's Mental Power is, the greater the frequency of their fluctuations. They can even alter their own brain's magnetic field to a certain extent and block me from entering."
An Qingyu fell into thought. "You can use your own magnetic field to influence other people's actions, but the duration of that influence varies from person to person... If that's the case, how did Jialan send you flying with a headbutt earlier? Don't you lack a physical body?"
"I find that strange too." Jiang Er touched her forehead, her eyes filled with confusion. "Since she could knock me away, there's only one possibility... she adjusted her own brain's magnetic field to be exactly the same as mine.
"And to do that, two prerequisites are needed. First, her Mental Power must be strong enough. Second, she must have been possessed by me before and become familiar with my magnetic field's fluctuations in order to replicate them... But I've never possessed her, have I?"
"Could it have been a coincidence?"
"...Perhaps."
An Qingyu nodded. "Then what did you talk about back at