Yunoki has not only found himself in bed with a woman he doesn't know, but she insists they're already a couple?! The woman, Kotoka Hatsushima, is a charming,23-year-old writer...who has one heck of a back fetish, and Yunoki fit the bill! And when she tells Yunoki that it was her hair that sealed the deal for him, he realizes the truth—she knows about his hair fetish, AND she's absolutely right! He's mortified, but Kotoka sees reason—if they float each others' boats and already know about each other's predilictions...why not start a relationship? And Yunoki can't argue with that...thus the back/hair (not to be confused with back hair!) hijinks ensue!