Starring the tomboy Kathy and her friends doing lewd things with her uncle.
Part 1: https://www.pixiv.net/member_illust.php?mode=medium&illust_id=61923192
Part 2: https://www.pixiv.net/member_illust.php?mode=medium&illust_id=64753058
Part 3: https://www.pixiv.net/member_illust.php?mode=medium&illust_id=64753058
Part 4: https://www.pixiv.net/member_illust.php?mode=medium&illust_id=71491373
