A series in which an older sister who has been active in bloomers when she was a student confesses her erotic acts at that time. This time, Mayu-chan, a G-cup busty beautiful older sister who can be seen even from the top of her gym clothes. She said she was bloomers until the third grade of elementary school in class, and even after the abolition of bloomers, she used it as an inner for school uniform skirts. While wearing such bloomers, I will immerse myself in bloomers play while talking about the naughty acts that I was secretly doing.