Maniac Circle Hakusho ~Hentai Shukujo-tachi no Monogatari~

The story of four heroines who belong to the “Pervert Club,” a maniacal circle of serious adult perverted gentlemen and ladies. The story of each of the girls who are currently active in the circle is depicted, including their daily lives, their motives for joining the circle, and how they came to be in it. There are a total of four stories, one each from the heroine's point of view, focusing on each of the heroines, with each taking the lead role. This is a six-part visual novel that continues to the story of the heroines' gathering at the circle, and finally the current story at the circle. From official site]