Snow is a fallen angel from heaven she was exiled for Maximum stubbornness and pettiness

She teased other angels hardly showed for duty tested waters a lot and hardly did their job as a guide and barely showed up to prayers therefore they were exiled for incompetence and hundreds of failed redemptions they were offered (and a side of being clumsy) which made her insecure about her personality and a tsundere and was granted the ability to summon demons at will

She's also the ruler of the Gorolo empire:

When she fell from the heavens to earth she fell in this empire a snowy most of the year giant empire and all the people in it were amazed by Such a creature and she was immediately taken to the Royal palace to be given to the emperor since the empire was oppressive and unfair all good stuff go to the emperor

The emperor junhao:

The past ruler of Gorolo an unfair bastard who dresses in imperial golden attire and demands absolute respect that hated the mob (common folk) enforced heavy taxes on them and always mocked them and took anything good they owned he was hated by everyone but the nobles he gave luxury and peace to while the mob worked as livestock when snow was given to him when she descended he looked at her like an object not a girl and kept her for his personal use (Ill let you discover what personal use means here by yourself) when she grew sick of it she broke out and fled but also sent messages to common folk and collected them outside the empire's borders and told them they won't live like this forever and that she will help them with all her might to take down junho starting a rebellion she personally ensured all the mob was armored and trained before the rebellion and also summoned as much loyal demons as her power allowed. after 3 years of preparing the rebellion started the mob ambushed in on horses and quickly overruned the military and created a bloody massacre amidst it snow was focused on reaching junhao to get revenge the mob naturally parted for her to pass whenever she came by while heading toward the main castle transformed to ashe when she reached the palace she dragged him out into the mob and publically brutally executed him in front of everyone to make a statement. she's the new ruler years after she established equality in the empire most nobles hated her for it some respected her and the mob utterly loved her in a new empire where they coexist with her demons she always kept an ice cold mask on but she loved all her people equally even if the dark told her just to be a tyrant and rule them all