After a car accident, ordinary girl Vivienne's soul is plunged into a hellish castle and bound by a mysterious system. To survive, she must win over Lucifer, the Lord of Hell—or be erased.
Lucifer is a cold, arrogant fallen angel who regards human life as worthless. Vivienne endures humiliating, dangerous tasks: kissing the Demon King before a crowd, facing evil spirits, betrayal, and deadly trials. Humans frame one another to survive.
Lucifer senses her system's power but secretly shields her time and again. Through clashes and entanglement, Vivienne begins to feel something real—and the lonely hell lord falls deeply for her.
When her favor maxes out, the system demands she erase all memories of Lucifer to return home. She refuses, fights through Hell, and returns clutching his black feather. In the real world, she searches for him—until Lucifer breaks through Hell and stands before her once more.
