Yuuji Fujiwara had an unlucky life. As a child, he was blamed for a vase he did not break, and he was fired from his job for a colleague’s mistake. At the convenience store where he works part-time, Takamiya-san, a younger girl, blames him for mistakes made by others. When he returns home in a depressed mood, he is greeted by a strange girl. When Yuuji is puzzled, the girl reveals her true identity. It turns out to be a mucus organism that has been living with him for the past three months. The creature, which speaks human language and can change its appearance, is in love with Yuuji. He is not at all pleased with the mucus life form’s affection. In order to attract Yuji’s attention, the mucus organism changes its appearance into Takamiya-san, the co-worker at his part-time job, and seduces him.