Description: The Sasazuka family whose parents are posted overseas. Because Kimihiko had to attend school, he and his younger sister Sarasa stayed behind, and he looked after her while they were away. Kimihiko is being hit hard by Sarasa. It's not that he hates it or anything, it's just that "calico'' has bothered him since he was a child, and it has become his daily routine. Due to this situation, he has developed a preference for "quiet masochistic girls'' who are the exact opposite of "chintz'', and for the sake of the masochistic girls who may appear someday, he buys SM adult goods. "What is this? What on earth is this naughty thing? I found it in my brother's room!" A set of goods is found by Sarasa...