After his master, Goomoonryong, destroys his ki-center, Shioon decides to leave the world of Murim for a normal life. But as the person who holds the Phoenix Medallion of the Sunwoo Clan, and the only disciple of the infamous Goomoonryong, the Murim world will not let Shioon leave so easily... 
Included Bonus Chapters: 48.5, 191.2, 200.1 (Epilogue), and 201.5 (Author's Note)

The new English teacher, Chun-Woo, is not your ordinary teacher. Shioon, a victim of constant bullying, unexpectedly witnesses Chun-Woo's fighting power, and begs him to make him his disciple. Chun-Woo claims he can teach Shioon only if he is truly determined, and Shioon must jump off a bridge into a deep river in order to prove it! 
It turns out, however, that Chun-Woo and his powers are more than meets the eye. Shioon makes a grand entrance into the hidden world of martial arts, and he is about to be taught by the best there is!

Ha-Je Kang can’t take it anymore. Pushed to the breaking point by relentless bullying, Ha-Je stands at the edge of the school roof, ready to end it all. But just as he’s about to jump, he’s given a push -- literally -- by a mysterious upperclassman named Si-Un Lee, only to wake up the next day, unscathed. Little does Ha-Je know that Si-Un happens to be one of the most powerful martial artists in the Murim, the hidden world of martial arts. Ha-Je begs Si-Un to train him, but he never could have imagined just how tumultuous things could get in the martial arts underworld… 
 
(Source: WEBTOONS, edited)

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