Nana, a cat, is devoted to Satoru, his owner. So when Satoru decides to go on a roadtrip one day to find him a new home, Nana is perplexed. They visit Satoru's old friends from his school days and early youth. His friends may have untidy emotional lives but they are all animal lovers, and they also wonder why Satoru is trying to give his beloved cat away. Until the day Nana suddenly understands a long-held secret about his much-loved owner, and his heart begins to break.