MKON-132 Mikan Kosuzu - I was at a physical therapy clinic with my girlfriend who has big tits, and I heard her say "Ooooooooooooooooooooooh

The protagonist, Shinji, has recently been experiencing stiff shoulders, and when he tells Mikan he's going to a chiropractor, she says, "That sounds interesting. Can I come along?" and decides to go with him. The two enter the chiropractic clinic, and Shinji checks in. However, the chiropractor says, "Your girlfriend might have a more serious condition," and "Women with large busts often develop more severe problems without realizing it," so Mikan also receives treatment. Behind the curtain...