In the original book, what was Nie Feng like after he was possessed?

Look at the last sentence of the first movie. Bu Jingyun and Nie Feng are fighting on the cliff. Bu Jingyun uses a sword and Nie Feng uses a magic knife. Finally, Bu Jingyun fell off the cliff and hit Nie Zhenlei's magic eye with his sword. He wanted to go to magic eye to exorcise demons first, which made Nie Feng change his mind. Bu Jingyun lost his memory after falling off the cliff, which is another story.