Even If This Love Disappears from the World Tonight

When Toru Kamiya is pushed into falsely confessing his
love to Maori Hino, she tells him she'll date him on three conditions. 1) Don't
talk to her until after school. 2) Keep any communication between them concise.
3) Don't really fall in love. Unfortunately, he isn't able to keep the last
rule' and when he tells her how he feels, she reveals that she has an
illness that prevents her from remembering anything that happened the previous
day, and that she uses a diary to keep track. But Toru is determined to build a
relationship with her, one day at a time.