Act 1 - Life ExpectancyEdit
Hisao first encounters Lilly in the tea room on his second day at Yamaku while trying to find the library. The two converse over tea and Lilly takes Hisao to the library, only to leave in a hurry after his first disastrous encounter with Hanako. Over the course of the week, Lilly helps Hisao adjust to life at Yamaku and the abnormalities of the students he encounters. Hisao also learns of the strained relationship between Lilly and Shizune. He and Hanako help Lilly and the rest of Class 3-2 prepare their noodle stall for the upcoming school festival. Later in the week the two meet one another heading into town and Lilly leads Hisao to the convenience store.
On the way back they meet a confused Rin wandering in the streets and bring her back to school with them. Lilly notices Hisao's exhaustion and learns about his arrhythmia, making her the second student to know of it - Rin being the first. The day before the festival, Hisao encounters Lilly in town with her sister Akira and learns that Lilly moved into the dorms last year to compensate for Akira's worktime. The day of the festival, Hisao manages to tempt Lilly away from her duties at the stall and enjoy the festival along with Hanako. As they watch / listen to the fireworks from the school grounds, Hisao asks Lilly if he can spend lunchtimes with her in the tea room. Lilly happily accepts.
Act 2 - PastEditThe day after the festival, Hisao joins Lilly and Hanako in the Tea Room and observes a game of chess, which Hanako wins. As they prepare to return to class, Lilly requests to feel Hisao's face. Lilly pronounces Hisao to be quite handsome much to the latter's embarrassment. Later in the week, Hisao learns that Lilly used to be on the Student Council, and that she is half-Scottish. She becomes brooding and awkward on the subject of her family but invites Hisao to go present shopping for Hanako's birthday.
That Sunday the pair goes into the city. While buying themselves ice cream, they encounter Akira and Hideaki, Shizune's younger brother and Akira's cousin. Hisao deduces that this means Lilly and Shizune are first cousins. Akira pulls Lilly to the side for a private discussion, leaving Hisao and Hideaki to wander around awkwardly. Hisao finds an antique store and purchases a doll for Hanako, then notices a small music box and buys that as well. After Akira and Hideaki take their leave, Hisao notices Lilly is more subdued than before. To cheer her up, he takes her to a cafe where they enjoy some tea and coffee. Both realize that what just happened qualifies as a date. Recognizing this subtle change in their friendship, Hisao offers to take Lilly out again sometime.
On the night of Hanako's birthday, Hanako is visibly moved after she receives the doll from Hisao and a teddy bear from Lilly. Akira arrives later with two bottles of wine and leaves soon after due to work. The trio give into temptation. Hanako passes out entirely and Lilly falls asleep on the bed, thanking Hisao for being there before passing out.
As they recover the next morning, Lilly tells Hisao that she is returning to Scotland for week because one of her aunts is sick. Lilly's parents left Japan because of her father's job six years ago and she hasn't seen them since. Lilly herself is sad, but seems to accept this part of her life. Hisao gives her the music box from the antique store and listening to its music seems to cheer her up. Before Hisao leaves, Lilly kisses him on the cheek as thanks for the music box.
Hisao doesn't get much sleep over the next few days. Shizune and Misha, after teasing him relentlessly for napping, give him a letter. Before he can open it, Hanako asks Hisao to join Lilly buy some groceries in town, as she has to study. During the sojourn, Hisao asks Lilly not to treat him differently because of his weak heart. That night, Hisao reads the letter. It's from Iwanako, bringing closure to the relationship they never had.
After a poor showing on his English exam, Hisao joins Lilly, Hanako, Emi and Rin on the rooftop for lunch. Between Rin's abstract butterfly comments and Emi's banter Hisao enjoys himself until he has a slight heart murmur. It passes, but the girls notice and Hisao feels guilty for worrying them. Later when they are alone, Lilly uses some lunchbag paper to make an paper crane. She learned origami to improve her dexterity and compensate for her blindness. Hisao recognizes what she is trying to tell him: pain exists in everyone's lives, and we must teach ourselves to cope with it. The next day, Hisao, Hanako, and Hideaki see Lilly and Akira off at the airport. Hisao resolves to do more to rebuild his life after its standstill in the hospital.
Act 3 - PresentEditThe days following Lilly's departure pass. Hisao asks Shizune about the conflict between her and Lilly. She coldly advises him to ask Lilly herself when she returns. Mutou interrogates Hisao on his plans after graduation, forcing him to confront the fact that he must plan for his future. Hisao hesitantly declares an interest in the sciences.
After class, Hisao takes some papers to Hanako, who was absent from class. Her failure to respond concerns him, and his anxiety increases when she is absent the next day. Worried, Hisao calls Lilly in Scotland for advice. She explains that today is Hanako's birthday, which is also around the time of year when her parents died. The same thing happened last year, and she regrets she can't be of more help. When Hisao prepares to hang up, she seems disappointed. Only afterward he realizes she expected him to call to talk to her, not about Hanako.
Hanako returns to class a few days later, back to normal. Reassured by this, and a "relationship talk" with Yuuko in the library, Hisao calls Lilly in Scotland. The two enjoy some small talk before Hisao tells Lilly that he misses her. Lilly replies in kind, affirming their mutual affection.
Hisao and Hanako meet Lilly and Akira at the airport. Since the Yamaku students have three days off from school Lilly invites Hisao & Hanako to her family's summer home in Hokkaido. Early the next day, the trio boards the early morning train to Hokkaido and arrive at the small summerhouse. As they spend time together, Hisao realizes he is in love with Lilly, and wonders when he should confess it. The trio decides to go into town, a mile and a half walk. Not long before starting, Hisao has an acute heart murmur. He suddenly realizes he forgot to take his medications yesterday. It passes, but the three return to the house.
After waking, he finds Lilly standing outside, alone. Lilly's calm demeanor cracks when she confesses her love for him. Hisao returns her feelings. Later they return to the house and as they talk Lilly insists that Hisao not apologize for his weak heart, as she does not apologize for her blindness. After some tentative invitation from Lilly the new couple make love.
Worried how this may affect Hanako, they sit her down and tell her of their new relationship. Hanako reacts with reserved elation. Later that day, Hisao takes a bath, and is interrupted by Lilly. The two bathe each other and end up having sex again. On the trip home Hisao realizes how much all three of them have come to depend on each other and wonders what they will do after graduation.
Act 4 - FutureEditOne day until exams, but Shizune and Misha are more interested in what happened to Hisao and Lilly over the holiday. He admits that they are dating. Misha seems happy enough, but Shizune reacts surprised. He and Lilly eat lunch in the Tea Room, reaffirming their mutual love. Later, they have a homecoming party in Lilly's room, with Akira and Hanako. Hanako reveals that she has joined the newspaper club, a welcome sign of her social development.
Later that week Hisao visits the nurse to discuss what happened in Hokkaido and leaves with some reassurance and advice. He and Lilly go to the convenience store and they bump into Akira along the way. She shows Hisao a photo of Lilly, Shizune, and Misha (with uncolored hair), working together at the previous Yamaku festival. Akira then tells Hisao she's leaving for Scotland soon, possibly for good. Lilly, already aware of this, becomes greatly subdued.
On Sunday evening, Hisao takes Lilly to dinner at a fancy European restaurant. Lilly mentions that she previously went to a wealthy, all-girls Catholic school. Despite this, several boys had confessed to her in the past. Hisao (depending on choice) tells her about Iwanako. Lilly reveals that, in middle school, she had a crush on her English teacher but never acted on it because of the social taboos. They both finish their meal and Lilly accepts the bill, saying that though she dislikes throwing money around, she'll make an exception for the special moment.
During an evening tea party Hisao, Hanako talks about plans to travel over summer with some members of the newspaper club. Hisao tells Lilly he plans to become a science teacher. After Hanako leaves, he asks Lilly if her blindness will affect her teaching. Lilly proves she will be fine by blindfolding Hisao and making him search for her. One thing leads to another and the two have sex, Hisao still wearing the blindfold. In his excitement, Hisao overexerts himself and collapses. Fortunately he recovers and the two manage a moment of peace. However Hisao feels Lilly growing more distant despite their relationship.
Hisao receives a call from Akira to meet her in the park. Akira talks about her resentment toward family, that they were rarely around for her and Lilly. She reveals that, while away, Lilly's family invited her to join them in Scotland. Odds are if she leaves, Lilly and Hisao will be unable to maintain their relationship. Hisao confronts Lilly about this on their date at the Shanghai. Lilly tells him that she plans to leave shortly after summer holidays begin. Hisao realizes how utterly futile their relationship was.
The day of departure arrives. Hisao voluntarily helps Misha and Shizune in the Student Council office. Lilly joins them one the last time, making a touching moment between cousins. After packing her things, the two of them meet Hanako and Akira front of the school gates. Lilly consoles Hanako and promises to keep in contact with her, and Hisao reminds her that she has her own life to lead. The Satous depart and while Hisao and Hanako prepare to move on, both are aware that something irreplaceable in their lives is now gone.
If Hisao was forthcoming and honest with Lilly in his choices, Hisao lays in his room, holding the paper crane Lilly had given him. He realizes how much he became dependent on her, yet failed to ever ease her burdens. Suddenly, Hisao gets up, determined to catch Lilly before she leaves. He takes a taxi to the Hakamichi residence, hoping they haven't left yet. Hideaki greets him, meaning they have already gone. However, he points out they only left recently and points in the direction of the airport. The taxi rushes to the airport. Hisao struggles through the crowds. Just as he spots her and Akira, his heart begins to fail. Hisao collapses, alarming various bystanders, and everything goes black.
Two days later, Hisao awakens in the hospital. The doctor explains that the attack wasn't as severe as the first, but he has had keyhole surgery to install a temporary pacemaker. With despair and angst at having ended up in a hospital again, Hisao falls asleep. He awakens to the sound of the music box he had given Lilly beside his bed. Lilly enters the room and emotionally breaks down. Hisao apologizes to Lilly for failing her and asks her to stay in Japan. The two promise to go to the next year's Tanabata festival together.
Some time later, Hisao is out of the hospital and sitting with Lilly and Akira on a hill near Yamaku. Akira plans to go to Scotland, but Lilly intends to stay in Japan. After Akira leaves, Hisao and Lilly return to Yamaku, ready to face their future together.