Shoukan o Suberu Yami no Kizoku ni Tensei Shita: Bishoujo-tachi to Nijuu Seikatsu no Harem Life

I was overworked and unlucky enough to be hit by a train and died.. However, before I knew it, I had been reincarnated in another world as a baby of the aristocratic Valsh family..! The level of civilization was about the same as that of modern times, and it seemed that they could live without any inconvenience. In fact, the valsh family has a secret family business, and at the age of fourteen, I became the boss of the mafia that rules the brothel.. !?