A convenient sex friend? Under the sun, An? An? An ◇ Under the open-air wind, Pyuu? Pyuu? Pyuu ◇ Edit!

The main character, Yu Arahama, who has five sex friends, Misako Shimizu, a colleague at the company, and Yanagi, who runs a coffee shop near Arahama's apartment. Ryoko, a schoolgirl she knows, Kotori Hoshino, and Makiko Endo, a female president of a large company.The five heroines, including Aina Kamishima and Misako, who met on a dating site, came to the beach at the suggestion of Arahama, who had gotten tired of having sex at her home. ``It's the ocean!'' the heroines exclaim, throwing off their clothes and diving into the ocean, each with their own watermarks already written underneath. The five heroines splash water on each other in the sea and bounce around with beach balls.