After drifting in during the 10th year of Taisho, Tsumugi is about to experience her first summer vacation. At the suggestion of Yuitsuki, she decides to go to a villa in Karuizawa, and she is thrilled by the first train ride and the unfamiliar scenery. In that travel destination, she meets a girl named Yukika, who seems to have had some past connection with Yuitsuki... The second volume where the wind of "S" blows into the Reiwa JK!