bal ance ▁of ▁f eng ▁sh ui ▁and ▁the ▁g hosts ▁from ▁the ▁hospital ' s ▁past , ▁so ▁a ▁ge oman cer ▁was ▁brought ▁in ▁to ▁construct ▁ 5 ▁am u lets ▁representing ▁the ▁five ▁elements ▁( W u ▁X ing ). ▁He ▁then ▁equally ▁spread ▁them ▁around ▁the ▁school ▁to ▁balance ▁f eng ▁sh ui ▁and ▁resist ▁the ▁spirits , ▁prevent ing ▁them ▁from ▁inter fer ing ▁with ▁the ▁living . ▁However , ▁it ▁also ▁locked ▁all ▁the ▁spirits ▁inside ▁the ▁school , ▁prevent ing ▁them ▁from ▁going ▁to ▁the ▁after life . ▁This ▁was ▁kept ▁a ▁secret ▁from ▁that ▁day ▁on wards . ▁One ▁spirit , ▁the ▁" Master ▁of ▁the ▁Lab yr inth " ▁could ▁not ▁stand ▁being ▁unable ▁to ▁escape ▁the ▁School s ▁hold ▁and ▁sought ▁a ▁way ▁to ▁escape ▁it , ▁eventually ▁using ▁the ▁body ▁of ▁Na - ye ong ▁in ▁ 1 9 9 7 , ▁threaten ing ▁that ▁she ▁could ▁never ▁leave ▁her . ▁ ▁One ▁day , ▁in ▁ 1 9 9 8 , ▁a ▁lab ▁fire ▁broke ▁out ▁in ▁the ▁Home ▁Econom ics ▁room , ▁resulting ▁in ▁the ▁death ▁of ▁Se ong - ah . ▁Se ong - ah ▁was ▁a ▁very ▁close ▁friend ▁of ▁Na - ye ong ▁( So - ye ong ' s ▁older ▁sister ) ▁and ▁died ▁because ▁of ▁her ▁ast h ma . ▁This ▁ups et ▁Na - ye ong ▁and ▁she ▁started ▁resist ing ▁the ▁master ▁of ▁the ▁lab yr inth . ▁Se ong - ah ▁became