Mio has been absent from school for several days, and everyone, even the Little Busters, seems to be gradually forgetting about her. Riki finally spots her in the courtyard again, but he notices an unfamiliar loneliness in her eyes...

When was the last time anyone saw Mio reading a book under the tree in the courtyard? What kind of person was she? Riki's memories become vague and he becomes scared that he might forget her completely. Will he be able to find the real Mio before she completely disappears?