In a town blanketed by snow, a place from his distant childhood, Yuichi reconnects with his cousin Nayuki. As she gives him a tour of his new home, he struggles with memories long faded.
After his first day at school, Yuichi is able to stir the memories of Ayu, who happily recalls a promise he made to her years before. But the strange girl who later attacks Yuichi doesn't seem happy at all.
Yuichi's attacker claims to have amnesia, and with the gaps in his own recollections and Ayu's forgetfulness, Yuichi starts to think the town might somehow alter people's memories.
Makoto's carelessness with a kitten causes Yuichi to lash out. Unfortunately, Makoto's response to his anger is to run away. Later, Mai somehow directs him to her likely location.
Makoto is growing weaker, leading Yuichi to increase the amount of attention he gives her. Her condition grave, Yuichi recalls Mishio's words - and he also remembers a fuller picture of Makoto's past.
Yuichi discovers Mai's bad reputation; she has a history of being blamed any time something bad happens on campus. Hoping to help her fix her image, Yuichi invites her to the school dance.
Yuichi's plan to salvage Mai's reputation seems to be working! With him in a tux and her looking radiant in her dress, nothing could ruin the school dance - except maybe the sudden appearance of a demon.
Yuichi's eager to defend Mai after her outburst at the dance, but someone beats him to it. His chance to play the hero dashed, Yuichi turns his attention to convincing Mai he's brave enough to fight alongside her.
Yuichi is throttled by Mai's revelation that the demons might come after him next. Sayuri is worried about both of her friends, but an attempt to surprise Mai on her birthday could end disastrously!
After fighting their way to the last demon, Mai mysteriously disappears and Yuichi is floored by an invisible force that conjures up visions of the past - and reveals a shocking secret!
Yuichi decides it's time to make good on his promise to Shiori. The two friends enjoy a day of snowball fights and whack-a-mole, but Yuichi's evening is marred by tragic revelations.
Yuichi desperately wants to make Shiori's birthday special, but he can't seem to think of how - until a chat with Ayu provides just the right inspiration.
Hoping to make her final days special, Yuichi hatches a plan to surprise Shiori with a birthday party on the day before her birthday! But there's one thing he must do first - convince Kaori to attend the party.
Yuichi sees Nayuki in a different light when the final track meet rolls around. Later on, Ayu and Yuichi's search for the all-important missing item leads to something very special.
Still basking in the glow of their kiss, Yuichi and Ayu spend more and more time together. Everything appears to be going splendidly - until their burgeoning romance is derailed by a visit to Ayu's school.
Ayu's disappearance prompts Yuichi to search even more diligently for her missing item. Nayuki goes out of her way to cheer up her heartsick housemate, but she my regret requesting strawberry cake.
Grief-stricken Nayuki locks herself in her room and refuses to let anyone enter. Tragic memories concerning Ayu wash over Yuichi, causing him to wander into the woods during a snowstorm.
Yuichi is still searching for Ayu. Akiko may hold the key to discovering her whereabouts, but will Yuichi be able to handle the truth about her current condition?
