MKON-115 My girlfriend who came with me to the massage parlor said 'Big boobs cause shoulder stiffness,' so we decided to get treated together... I heard moaning from the other side of a curtain... Hatsuki no Ao

The protagonist Yuusuke has been having stiff shoulders lately and told Nao, 'I'm going to a chiropractor.' Nao replied, 'That sounds interesting. Can I come with you?' So they decided to go together. The two entered the chiropractic clinic and checked in. However, the chiropractor said, 'Your girlfriend might be more severely affected.' 'Women with larger busts often develop severe conditions without realizing it.' Thus, Nao also decided to receive treatment. From behind the curtain, Nao's voice could be heard: 'Oooohhh!! Ohhhh!!! Ooooohhhh!!!' What kind of treatment is she receiving?!