The protagonist, Yuutenji Shirou, raised his own daughter by himself after his wife abruptly died in a traffic accident.
Not yielding to the hardships of being a single parent, he earnestly raised her daughter Ayako, who is his pride and joy. However, after she reached adolescence, she doesn't listen to him much, and so recently, their daily life is filled with sighs.
After telling her daughter that he got confessed to by a subordinate, their life completely changed.
Late at night, Shirou woke up to a strange feeling, and realized he can't move as both of his arms were tied. Ayako told him she saw him as a man, and before he knew it, he had sexual relations with his own daughter.
Unable to talk to anyone about his problem, Shirou carried it alone. Her restraints unbound, Ayako sought after his body almost every night.
Can Shirou break away from this forbidden relationship, or will he...?