Onui is concerned for Shunpei having to worry about his mistakes in his calculations. The old man tells the story about Naje-Naje, a curious boy who, after pestering the villagers with questions, sets on a dangerous journey to seek the answer to the ultimate question, though the old man leaves it as a cliffhanger. Shunpei goes out with Onui to ask various residents about his stress, but to no avail. The next day, the two talk to Toyama, Oise, and Oriku, yet they were no help either. Shunpei reminisces of when he used to play with a dog as a child. He wished to be able to run away with her when his parents were fighting, but needed to stay because he wanted to solve a math problem. It is implied that Onui was the dog from Shunpei's childhood.
「割り切れない」が口癖の駿平。そして駿平がかわいそうなおぬい。そんな駿平たちに、ご隠居が好奇心の強い少年・ナジェナジェの例え話をして聞かせる。なぜ、自分はこんなにも悩んでいるのか、その答えを探しにナジェナジェは冒険の旅に出たのだと。これを聞いたおぬいが、彼のナジェナジェ探しに駿平を連れ出して…。
