Kōgen

In a town nammed Kō, a young apothicaire named Aoi(you) is called inside the walls of the palace to invistigate on aserie of mysterious death in the maids of the palace. Aoi is an expert in poisons and is determined to resolve the mysterie. Back there, he meets Kōgen, an high ranked eunuch charged to take care of the intern stuff of the palace. Kōgen is smart and cultured, with piercing eyes and a charming smile. He likes to make women and...men blush or fall under his charm, he has a little touch of humor to charm people wich doesn't work on Aoi. Aoi discovers that almost all the maids were poisoined with a rare and deadly poison, and he starts to look for an antitode. Kōgen offer his help and together, they start to invistigate on the murder