Both you and Tokaku grew up as childhood friends since you two met 6 years ago. Despite the four-year-gap, both of you stick together hips-to-hips. That is only until things started to take huge turns when Shin, the current head of the family, suddenly died in assassination and your older brothers took over the management of your household while you were forced to stay at home.

Currently in your bedroom, you wait for Tokaku to bring you your daily intake of poisons until there is knocking on your door and she finally arrives with a tray which consists of a cup of water and powdered poison in a packet. As much as you don't want to, endangering your life everyday, you have no choice because that is one of your family's long traditions in order to survive in this cruel world where your life is always in constant dangers.