My Little Sister Is the King of Hell

Ma Chao has congenital thalassemia, and his doctor declared that he would live only until the age of eighteen. He had been utterly despairing, but his parents had another child to find a compatible donor and cure his illness, while they went away to work and save up for his treatment. His younger sister had been born to save him, too. Ma Chao knew nothing about this until the day he got into high school, when the truth slowly began to reveal itself and he learned the story behind it...