Chapter 1

Plot
We are introduced to 16-year-old Hajime, who, after suffering a traumatic experience in making friends, decides to ditch making friends altogether during high school. Meanwhile, the mouse Lunar lives in the underground world of rodents. Her grandmother Moon tells scary stories about the evil nature of the cats that live in the outside world, though Lunar doubts that they are entirely true. She loves to draw but must soon study medicine, which is what her grandmother does as well.

During school, Lunar's classmate Anna was ranting about cats and their lifestyle. Anna warns Lunar that cats and mice can never form a bond. After school, Lunar travels above ground to discover the world of cats. On one such occasion, an elderly cat merchant family catches Lunar in the act and chases her into a trash can where she is trapped and spends the night. That night, a starving Hajime discovers Lunar and attempts to eat her. The bold Lunar convinces him to let her go and bites him, letting her free back to the underground. While underground, Lunar suddenly becomes curious about the feline Hajime.

Events

 * Lunar meets Hajime.
 * Lunar becomes eager to know about Hajime.
 * Lunar travels above ground for the first time.