C.O Lee 
Maeum’s Wish [EPUB ebook] 

Maeum has lived in the hole in the ground with all the other humans for all her life. All that she knows is from living in the hole in the ground. While conformity is the standard within the dirt walls, Maeum finds herself wandering about and daydreaming instead of following along. When a guide comes along in the form of a sparkly cat and insists that it’s a masul, Maeum takes the chance and leaves the hole in the ground for the first time.