Subaru has begun living with a cat as a roommate. He realizes he's run out of cat food and goes to a pet shop to buy more, but starts to panic when he's surrounded by creatures he's never been around before. Then Nana, a shop employee, starts to talk to him, asking him questions about the cat's name and age. Subaru then realizes he hadn't thought of a name for the cat yet. Nana tells him that he should give the cat a name because it's his family now, so Subaru tries to think of one, but nothing good comes to mind. As he's pondering, he comes across a book in his room called "The Moon and the Sun"...

Subaru is at home doing his favorite thing, reading... but then Hiroto and Kawase show up, robbing him of his time alone. Then Kawase suddenly orders Subaru to buy a collar for Haru immediately, saying it'll help identify her in the event that she gets lost. So Subaru heads for the pet shop, where Nana helps him find a suitable collar. But Nana also tells him that many cats dislike collars and only end up stressed out by them. Will Haru approve of her new collar?

Subaru's return from Tokushima is delayed by stormy weather, so he asks Hiroto to check in on Haru. Meanwhile, Haru is growing worried over Subaru's unusually long absence... so the moment Hiroto arrives, she bolts out the door to look for him! When Subaru hears this, even the driving rain can't stop him from rushing to search for her. Nana, Yugo, and Kawase also join in the hunt, but Haru is nowhere to be found... Will Subaru and Haru find each other again?