The story revolves around a young man named Yoo-Joon, who makes a desperate deal with Anny, an immortal witch, to save his sister Dam's life. In exchange for Dam's life, Yoo-Joon agrees to give his soul to Anny. As the story unfolds, we learn about Yoo-Joon's troubled past, his sacrifices for his sister, and his encounter with Anny. Anny, a complex character with a mysterious background, displays a mix of selfishness and compassion. She helps Yoo-Joon, but her motives remain unclear. Throughout the narrative, Yoo-Joon grapples with his emotions, fears, and doubts while navigating the consequences of his pact with Anny. The story explores themes of sacrifice, love, and the blurred lines between good and evil.