One morning, on her way to school, carefree, daydreaming Yua Serufu wrecks her bike and an upperclassman comes to her rescue—a chance encounter which sends her down a path to answer the question, "What does 'DIY' mean?"

When Purin sees Jobko through Serufu’s window, she heads over and gets introduced to the girl genius. The two end up hitting it off. Then, the next morning, Purin wakes to find Jobko in her room saying that she’ll be living there—effective immediately.

The heat and humidity of the rainy season make it difficult for the DIY club to get any work done, so Kurei invites everyone to her house for air conditioning. When Serufu and the others visit Kurei’s room, they discover a surprising side to her.

The DIY club holds a celebration at their newly completed secret hideout. Then summer vacation starts and Jobko heads home, promising she’ll see everyone again. Purin takes Serufu to the DIY club, saying that the secret base is still missing something.