Kota visits his childhood friend Saki Aikawa's house for the first time in a while and accidentally discovers her mother, Saki, masturbating. She had always seemed kind and gentle, but her current appearance had transformed into something entirely different and alluring. Captivated by the seductive scene, Kota pulls out his smartphone and takes photos. At that moment, a dark, unfamiliar desire begins to stir within him. He wonders if showing her these photos might make Saki give in to him. Excited by the possibility, Kota feels his heart race. Tonight's events will bring a major change to his life.