For the people, terror lurked within the night.
Each night was hard to get through in peace. Even a cat's meow coming from the yard could be some strange creature of the night, silently approaching those who had forgotten to place divine symbols on their doors.
And for the deities, the long nights were apt to nurture heart demons. Many deities, in their cultivation process, might have done things that defied the Heavenly Dao. Even if they later disciplined themselves strictly and constantly used their strong willpower to resist the expansion of the heart demons, the chilling darkness and sinister energy of night were the dew that nurtured the heart demons.
Heart demons always resided within the divine souls of each deity, like a healthy body accumulating bad habits over time, eventually becoming chronic illnesses. Not to mention those deities that were already twisted in nature, filled with hatred, resentment, frustration, humiliation, greed...
