The story begins with the main character, Ic, being accused of murdering his girlfriend Mari. As the story unfolds, it is revealed that Ic has grown horns after a night with a mysterious woman, and these horns have the power to bring out the darkest secrets in people.
Ic uses the horns to uncover the truth behind Mari's death and discovers that his best friend, Lee, was the one who killed her. Lee had been obsessed with Mari and misinterpreted her actions, leading him to murder her.
Ic seeks revenge against Lee, but not before discovering that Mari had been keeping a secret from him: she was terminally ill with cancer and did not want to burden Ic with her illness.
In the end, Ic confronts Lee, who is forced to confess to the crime. Lee is then killed by Mari's father, who had discovered the truth. Ic, driven by anger and a desire for revenge, transforms into Satan and kills Mari's father.
However, the story takes a surprising turn when Ic is mortally wounded and dies in his brother's arms. As he dies, he is able to free himself from the evil that had consumed him and is reunited with Mari in the afterlife.
Here are the key facts extracted from the text:
1. A young couple, Mari and the protagonist, were in a relationship since childhood.
2. The protagonist woke up one morning to find many people accusing him of being a murderer.
3. Mari was murdered, and the protagonist was accused of the crime.
4. The protagonist discovered he had grown horns after a night of drinking.
5. The horns gave him the power to make people tell him their darkest secrets.
6. The protagonist went to the doctor to remove the horns but was unsuccessful.
7. He remembered meeting Mari in church and how they became inseparable.
8. Mari broke up with the protagonist before her murder, and he was devastated.
9. The protagonist discovered that his brother, Terry, was with Mari on the night of her murder.
10. Terry had been in a secret relationship with Mari and was the one who murdered her.
11. The protagonist used the power of his horns to make Terry confess to the crime.
12. The protagonist's friend, Lee, was also involved in the murder and had been in love with Mari.
13. The protagonist took revenge on Lee and Terry for their roles in Mari's murder.
14. Mari's father believed the protagonist's innocence after hearing the truth.
15. The protagonist found a letter from Mari explaining why she didn't want to marry him.
16. Mari had the same type of cancer that took the protagonist's mother, and she didn't want him to see her suffer.
17. The protagonist decided to take revenge on Lee for his role in Mari's murder.
18. Lee was shot and killed by Mari's father.
19. The protagonist grew white wings but was consumed by revenge and became Satan.
20. The protagonist and Lee engaged in a final battle, resulting in Lee's death.
21. The protagonist died in his brother's arms but was able to free himself from the evil in his soul and reunite with Mari.