I'm staying with my brother and his wife. My sister-in-law, Aya-san, has always been kind to me and secretly had feelings for her... One day, when my brother goes on a business trip, we get caught in a sudden downpour! I'm left alone with my sister-in-law, who is soaked to the skin, in an empty, spacious house. Her hair is shiny and wet from the rain, the rainwater dripping from her clothes, and her voluptuous, wet chest... I couldn't take my eyes off her defenseless appearance. And then, losing my reason, I went with the flow and devoured Aya-san's wet and transparent body as I pleased...