A brief description of the Slave B manga:
The world is ruled and oppressed by the evil god Sekneum. Niro, a boy of the Half Elf race, born of an elf and a man who lost his parents, fell into the hands of a human slave as a baby. He grows up in a world where you can’t find justice for people. Having lost his father and mother, he soon becomes the head of the family, taking responsibility for two younger sisters. There is only one way to break out of hell slavery and protect his loved ones. To get out of the academy, as the Emperor here, a former slave, did. Will Niro be able to enter the Excanum? Will he be able to escape from despair?