She is an unpopular girl because she has a pair of heterochromatic eyes that can see everything.
She is both unlucky and lucky.
She was brought to another time and space by a car accident. In that space, everyone wanted her, but she chose him just because they were the same kind of people.
He is the Third Highness of the Demon Realm, an illegitimate son born between the Demon King and a human woman, an illegitimate son who is not recognized by the Demon Clan.
He is noble and sad.
The insults and bullying he suffered since childhood led him step by step towards the cold abyss. He practiced magic skills hard just to win his father's approval and smile, but what he got in exchange was ruthless ridicule. He completely blocked his heart, killed his father and brother, and climbed to the highest throne in the demon world step by step. He thought he would live a lonely life, but he met her who was treated the same as him.
Their treatment and experiences are so similar, but they are so different.