Thirteen years ago, a terrible monster known as the Poison Queen attacked the Kingdom of Jade. A brave group of adventurers managed to defeat her, but in the process, one of them was struck by a deadly curse. To survive, he was forced to pass it on to his own son.

Since birth, Kaim Halsberg has been despised as a cursed child, hated by everyone except his late mother and Tii, a maid who served his family. While his father and twin sister live in the family mansion, Kaim was forced to reside alone in a cabin deep in the forest. But everything changes when a certain "doctor" helps him overcome the curse and awaken his dormant power.

Now reborn as the King of Poison, Kaim sets out on a journey to fulfill his one true wish… though he never imagined his poison would have such a peculiar effect on the beautiful women he meets along the way!