As Jinwoo continues his training, he completes a daily quest one day by doing more than the quest requires, and a key that leads to a certain item appears in front of him.
The Demon's Castle... 
Acquisition difficulty S?!
!قلعة الشيطان... صعوبة الاكتساب س؟
"Castillo del Demonio".
"Castillo del Demonio".
Il castello del Demone...
"Castelo Demoníaco"?
«Дьявольский замок»…
Редкость — S?!