The poster's hobby is taking pictures of his busty girlfriend Mayuri with G-cup breasts. At first, he took pictures on his cell phone as a joke, but then he set up a hidden camera in his house and started taking pictures of her when she came to stay the night. He gradually opened Kokoro to her and filmed her cooking, giving him a blowjob on his cell phone, and taking pictures of them taking a bath together and peeing, and recorded her over a long period of time until she finally agreed to film him having sex.