Lailah is an archangel and Emilia's mother. 300 years ago, Lailah rescued a young Satan from the brink of death as she had never seen a demon cry before. Despite his protests, she nursed him back to health, at the same time sharing stories and knowledge to his unwilling ears. Satan learned of humankind through Lailah. She left secretly, leaving him a note along with a fragment of Yesod, a purple crescent-shaped crystal, and told him to plant it if he wanted to know more about the world. Lailah was the first to call Satan "The Great Demon Overlord, Satan" with a note. Many years later, Lailah met Nord Justina. Once she had given birth to their child, Emilia, she entrusted Nord and Emilia with 2 other fragments of Yesod and left to avoid capture by other angels.