Pianist Misaki opens a piano class at home with the support of her understanding husband while performing. One day, Misaki notices that she is out of tune and consults with a tuner she is familiar with, but unfortunately she has her hands full. She is introduced as "her skill is certain", and she asks her tuner named Kagiyama for the first time. However, she got angry at Kagiyama's overly rude remarks and tried to turn him away, but...