Tohru is a young man aspiring to become a pornographic writer. He has an older sister three years his senior, whose allure constantly captivates him. Every day, he secretly records scenes of his sister and her boyfriend interacting, capturing their ordinary moments with a hidden camera. His mind is endlessly consumed by images of his sister, driving him into unbearable torment. Struggling to suppress his urges while striving to perfect his work, the story delves deep into Tohru's inner conflict. As daily life and desire intertwine, a poignant yet intense tale of forbidden passion unfolds.