A female college student was taking selfies at home while wearing school swimwear over her tights, and then her younger sister came to visit, so...

Furukawa Kei, a university student, has had a new fetish awakened by his childhood friend Shirasawa Kanako, and has been taking selfies while wearing a school swimsuit layered over tights. Then his younger sister, Furukawa Ai, comes in... ※To be honest, this is just a story where a girl was taking selfies in a school swimsuit over tights, her younger sister found out, and then gets dragged into the rabbit hole.