Let's make a contract, Demon Fox

The modern girl fell in love with the demon fox king with a deep hatred of the sea of blood and broke into the demon world for him.
"Come on, let me be your blood covenant signator! From now on, I won't leave you alone anymore!"
God's ice and plum blade cut off fate
The mountain of knives and the sea of fire depend on life and death

She was his life-saving benefactor ten years ago, but she never thought that the little fox she saved at that time was the descendant of the demon king fox, the lord of the demon world.
He has been burdened with a cursed fate since he was born. He grew up alone in deception, but he can't forget the human girl's life-saving kindness to him in any case.
They met again on the high school campus...