Due to my mother's remarriage, my sister and I gained a stepfather. However, one day I stumbled upon him assaulting my younger sister (a high school girl), and I discovered he was a lolicon. To protect my sister and not sadden my mother, I made a promise: "As long as you don't touch my sister, you can do whatever you want with me." From that day on, to avoid being exposed in front of my family, I endured being manipulated physically, repeatedly being stimulated with obscene toys, and subjected to in-house humiliation plays... Eventually, my body began to feel something for the play with my stepfather...