During summer vacation, Shota was invited by his friends to go to the beach, but due to sudden weather changes, the beach was closed and their plans were canceled. Seeing his friends disappointed, Riona, the older sister of one of his friends, decided to buy a home pool to cheer them up. On the night the pool was set up, Shota caught sight of Riona's swimsuit, the tight fabric barely containing her overflowing curves, and his cock instantly swelled up hard and thick. In this charged atmosphere, their relationship began to deepen even further.