Synopsis: How to Use an Angel

Yoon Kiom, a 24-year-old, finds herself in an unexpected and precarious position after performing a rare act of kindness - being chosen as the sacrifice in a demon summoning ritual. As the ritual commences, Kiom is taken aback when an incredibly powerful being crashes through the wall, encircled by a radiant light. Initially, Kiom hopes the stranger will rescue her, but she soon realizes he has no plans to do so. Instead, he addresses her as Sion and appears disturbed by her very presence. Kiom acknowledges that the man is strikingly attractive, appearing as an angel with his sword at the ready. However, she can't help but wonder what terrible misdeed she must have done to cause an angel to threaten her with death.