After being pushed by classmates into making a false confession to Maori Hino, Toru Kamiya begins a pretend relationship on the condition that neither of them truly fall in love. He soon learns that Maori has anterograde amnesia and loses each day's memories when she sleeps, so he starts building a love that lasts only one day at a time.

A young love story about choosing to build memories one day at a time, even knowing they will be forgotten.