Graduation draws near for Yui, Ritsu, Mio and Tsumugi, the four 3rd-year students of the Light Music Club. They, together with Azusa, decide to go on a post-graduation trip. Their destination, decided by Lot, is London!

The protagonist of the story, Konoha Inoue, is a seemingly normal senior high 2nd year student. His high school life, other than a hinted incident 2 years ago, can be summed up as normal- if one can dismiss the secret fact that he used to be a female bestselling romance author. Due to that incident, however, he has now vowed never to write again. This continued on until he was forced to join the literary club by the literary club president, the 3rd year female student Amano Tooko, a beautiful girl who has a taste for eating literary works. Now he has been tasked with writing her snack every day after school. (Source: To Say Nothing of the Dog)

Bincho-tan, an orphan lives alone in the forest, she always has a piece of coal bonded on her head. Occasionally, she ventures into the town situated near the mountain, in search of work opportunities. In gratitude for her work, the townspeople offer her food as a gesture of appreciation. Bincho-tan leads a challenging life, but her joyful and warm demeanor endears her to those around her, leading her to make new friends. As time goes on, one after another heartwarming stories unfold, Bincho-tan finally illuminates her smile like a happy child.

Mai is a grade-school girl who tries to understand her family better.