병약한 남궁세가 도련님은 흑화한 옛 제자가 무섭다 (Associated Names)

In the past, Eun-hyeon was transported into a martial arts novel called “Descent of the Heavenly Demon” where he raised the protagonist, Cheong-un, as his disciple. Unlike the original story, Eun-hyeon formed a good relationship with his disciple but eventually died following the original plot, and returned to reality. In the real world, Eun-hyeon had…