Karada wa Jidou, Nakami wa Ossan no Nariagari Boukenki

Born as the third son of the poorest noble in the empire, Grey Millard faced a difficult childhood. His stepmother, a fiendish woman, manipulated his feudal lord father within the confines of their Millard territory, leaving Grey feeling uneasy about his family's situation. At the age of just 13, Grey made the bold decision to sever ties with his parents and leave the territory behind. He dedicated all his time to self-improvement, however, in doing so, he overlooked the suffering of those oppressed by his stepmother's tyrannical rule. But this was only the beginning of the journey for the wise-beyond-his-years boy.