ご主人様は妹ですか？ ～Ｍっ娘好きの俺が、なんで妹のＭ男に！？～

The Sasazuka family whose parents are posted overseas.
Because Kimihiko had to attend school, he and his younger sister Sarasa stayed here and looked after him while he was 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 come to like “quiet masochist girls” who are the exact opposite of “chintz”. He had been stocking up on SM adult goods online for the masochist girl he was destined to meet someday, but one day…