So far this is the only route that doesn’t get a further explanation. It’s still pretty obvious if you look at the hints, but still.. it left you wondering about the truth.
Tohno Haruka is a sheltered ojou-sama and one year younger than Nagisa. She’s the daughter of Tohno Kousuke, the leader Tohno Group, who owns a large portion of major business in the island. Her body is weak, and she is currently under medical care in a church in the woods with her maid Aria. She had a dream of opening her own shaved ice shop and also likes roleplaying.
Because of her health condition, she couldn’t attend school most of the time. It makes her happy when the skin diving club members gather and do fun things together. Though usually hanging out with the energetic Hitsuji makes her tired, she enjoys spending time with her friends.
Knowing her own condition, dying is as close to Haruka as living. She wanted to do the things she’d love to do while living, so that when she dies she would die happy. Haruka wished for Nagisa to find something that he wants to do too. In the end Nagisa decided that he wanted to visit Haruka everyday. After he saved her from falling from a cliff, Haruka realized that she wanted to stay with him too.
After they started going out, Nagisa often spent the night at the church. Haruka eventually got pregnant with his child. With her physical condition, delivering the baby safely would be very difficult. Even so, Haruka herself wanted to give birth to their child. She wanted to live like cicadas. Coming out from the ground, living their short lives fully and give birth to their children before going back to the ground.
Even since she was small, Haruka didn’t know until when she would live. In this island where it’s Summer all year long, she felt like she could live healthily even though she know her life might not be that long. For Haruka, having a child with Nagisa was her future. So even though she dies later, their child would live on.
Aria was against the idea though. Fearing for Haruka’s life, she even went as far as accusing Nagisa as a murderer if Haruka dies giving birth to their child. Haruka slapped Aria, telling her that she decided to give birth to meet their child. The next day, Aria disappeared. She left a memo asking Haruka if she found her dream already. It also said that she’s always by Haruka’s side, so someday they would meet again.
Haruka then revealed that Aria was not a person employed by her family. Haruka herself used to live with her grandfather after her parents divorced. That year, her grandfather passed away. Haruka came to the island to live with her uncle, but since she didn’t want to burden them with her health conditions. Haruka reached the church while wandering around and met Aria there. They started living together in the church, with Aria taking care of her.
A few days after they started living together, they met Nagisa.
After Aria disappeared from the church, Nagisa spent the days with Haruka. He often had the thought to bring her to the hospital, but she always refused. Then one day, Haruka woke up and asked Nagisa to fulfill her third wish. In a dream she had earlier, she was a cicada that hopped in the big tree Christmas. She made a wish to Christmas to take her remaining, short time and change it into her child’s future. So that her loved one and their child could walk hand in hand after she’s gone. Haruka then apologized to Nagisa, since there was no more time for her. She didn’t have more time to stay with Nagisa, nor to give birth to their child. Her wish was for Nagisa to wish for that dream to come true.
The next moment Nagisa opened his eyes, he was lying on a small boat below Christmas. Haruka was asleep beside him, along with their newborn little girl. Haruka woke up and said she was a cicada. A happy cicada that fell in love with him and met with their daughter.
The epilogue shows a little girl (who bears a striking resemblance to Aria) talking to her father, Nagisa. She told him that she dreamed about her mother. It’s weird how she knew it, even though she never met her mother. The little girl thought it must be fun if her mother is still alive. But, even though it feels lonely that she couldn’t meet her mother anymore, she really enjoys being with her father. The girl then thanked Nagisa for being with her.
Judging by Aria’s reaction, she is Nagisa and Haruka’s child who came from the future. It seems like she blamed him for letting Haruka give birth to her, which resulted in her death. Her purpose of coming back to the past is unclear since it wasn’t explained, but it might be because she wanted to protect her mother.
After seeing how Haruka herself wanted to give birth to her, just to meet her and let her live, Aria realized that all Nagisa wanted was for Haruka to be happy. When she disappeared, it might be that she went back to the future using Christmas’ power. In the epilogue it shows how much she loves her father though. Maybe because she realized that both of her parents wished for Aria to enjoy her life and future, in change of her mother’s short life.
I wish they’d give more explanation, but the story is good nonetheless. It’s too bad that it wasn’t a really happy ending since Haruka died in the end, but Aria’s love towards her father made up for it. For me, at least.