Japari Park is an untamed paradise where many humanoid animals, known as "Friends," live their everyday lives in all corners of the natural environmental park. One lazy afternoon in the savannah area, the energetic Serval encounters a peculiar new Friend. Curious, she swiftly takes down the Friend, named Kaban, to try and discover what species she is. To Serval's disappointment, not even Kaban herself knows the answer. The two become friends and set out on a grand adventure through the many habitats, landmarks, and attractions of Japari Park. Their destination is the park library, where they hope to shed some light on Kaban’s identity. Along the way, they meet many other Friends, looking into their lives and helping them out. However, they soon begin to uncover the sinister reality behind the park and their own existence.

A few young girls with strange powers and a tree that has grown through a railcar cling onto life in a desolate land, searching for its last reservoirs of water. Their routine struggle to survive is interrupted by the arrival of Wakaba, a boy with no memory beyond his own name. The girls and their new companion commit to a perilous journey across seas of burning red fog—all in order to find what they need to sustain themselves on the more distant, dangerous islands swarming with robotic bugs. Their ultimate fate will be decided by their own strength, along with Wakaba's curious ability to understand the Kemurikusa: mysterious glowing leaves with wondrous powers. Besides the girls, Wakaba, and the hordes of ravenous bugs, the Kemurikusa are the last sparks of life surviving in this land. How did things end up this way? Why are there so many empty buildings with no one to live in them? Wakaba and the girls lack the answers to these questions, which means the truth can only be found within the Kemurikusa.