Flower, the legendary assassin. He is cruel, ruthless and has no mercy on women or children. He is said to have honed his killing skills in Mexico and to disappear after leaving a flower at the scene of a murder. No one knows what this means, but Flower's name has become an urban legend in the underworld. One day, Momoko, a female assassin, receives a request to eliminate Flower and confronts him. However, her true identity is completely different from the rumour.

伝説の殺し屋・フラワー。それはメキシコで殺しの腕を磨いた残虐で無慈悲な人物とされていた。殺人現場に一輪の花を残して姿を消すフラワーの真の姿に迫るべく、1人の女殺し屋・モモコが追跡を開始。やがて姿を現したフラワーは、噂とは全く違っていた。