The protagonist, Shinji, has been suffering from stiff shoulders lately. When he told Mikan, "I'm going to the chiropractor," she replied, "That sounds interesting. Can I come along?" and joined him. After Shinji checked them in at the clinic, the chiropractor remarked, "Your girlfriend might be in worse condition." He added, "Those with large breasts often become severe cases without even realizing it." Consequently, Mikan also received treatment. From behind the curtain, strange voices like "Ohhh, Ohhh!!? Ohhh!!? Ohnnn, Ohhh!!?" began to echo. Just what kind of treatment was she receiving!?
