Rei has a daily habit of writing sensual diaries, frequently filled with thoughts like "I want to be fucked by my son..." Though she herself isn't sure whether these feelings are genuine, the words are more than enough to ignite strong emotions in her son, Kyohira. One day, Kyohira discovers her diary, and its contents quickly transform into reality. Kyohira repeatedly fucks Rei, filling her with creampie after creampie until she's overwhelmed. Rei gradually loses the boundary between fantasy and reality, drawn deeper into this twisted relationship. The story unfolds with an intense, captivating progression that pulls the reader in.