ef: A Tale of Memories.

Synopsis

Chihiro tells Yuko and Kei about Renji. Kei wakes Hiro and forces him to get up and go to school. While ditching classes, Hiro runs into Miyako again, and finds out that they are in the same year at the same school, though in different classes. He tells her that the reason why he does not attend classes much is that he is already an established manga author. Kyosuke continues to ponder over the brief shot he got of Kei running through the city on Christmas, though he does not recognize her. Renji meets again with Chihiro and becomes closer with her. He eventually finds out from her that she has a memory defect where she cannot remember anything past thirteen hours previous.

(Source: Wikipedia)