When Toru Kamiya is pushed into falsely confessing hislove to Maori Hino, she tells him she'll date him on three conditions. 1) Don'ttalk 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 lastrule‚ and when he tells her how he feels, she reveals that she has anillness that prevents her from remembering anything that happened the previousday, and that she uses a diary to keep track. But Toru is determined to build arelationship with her, one day at a time.