01. An Awful Birthday
July 1st, 2030. Manga editor Nishino Mizuho is having the worst 27th birthday ever. The manga she’s in charge of will be ending. However, when she sees a group of high school students having fun, she recalls her own adolescence. 10 years ago, during her second year of high school, Mizuho had four childhood friends who she grew up with in a residential neighborhood known as Koigahama Highlands…
02. I'll Be by Your Side
Kizuki, who Mizuho saw as the crybaby little brother of the group, has lately been hitting on her. Since Mizuho believed her and Kizuki would be childhood friends forever, she is not sure how to approach this situation. He's on her mind to the point where she seems disoriented, and even says something that could potentially push Kizuki away.
03. Warmth
Afraid of ruining their relationship, Mizuho tells herself not to fall for Kizuki. All the stress makes her ill, and her friends come to help.
04. Fireworks for the Future
After spending the day at the aquarium, Kizuki asks Mizuho to cheer for him at his swim meet.
05. How to Be Together Forever
As the fireworks are set off, Mizuho rushes to look for Kizuki. At the pool she runs into...?
06. I Don't Want to Be Just Friends
Mizuho is reluctant to visit Kizuki's house for dinner while her dad is away.
07. Playing Nice
Shugo's older brother, Togo, makes a surprise return to Koigahama Highlands.
08. The Shape of One-Sided Love
Mizuho goes out with Shugo and Togo and strongly contemplates her feelings for Kizuki.
09. The Times I Spent With You
Shin steps up as the student council president to ensure the Ao High Festival can be held.
10. Impulse
The group goes on a camping trip! Airu tells Shin to be more selfish and he follows his suggestion.
11. Things That Change
Mizuho starts becoming aware of Shin's intentions after he kissed her at the campsite.
12. Neverending Dream
Shin and Kizuki compete over Mizuho. Meanwhile she finds out the results of the Newcomers' Manga Competition.
13. The Fireworks Ten Years Later
The year is 2030. Mizuho hasn't heard from Kizuki in years. But at the fireworks festival, she bumps into...?
14. I Can't Give Up
Mizuho reminisces the day her and Kizuki started dating. Shin approaches Mizuho with his feelings once more.
15. My True Self
Airu takes a chance and confesses his feelings to Kizuki and his delinquent past is revealed.
16. A Miracle
Mizuho believes her relationship with her friends could fall apart due to her dating Kizuki. However...
17. Feelings That Won't Go Away
The seniors graduate and celebrate their last day at the pool, leaving behind heartfelt messages.
18. I've Liked You This Whole Time
After a fight breaks out with Syugo and Kizuki, the friend group reunites for the first time in years.
19. I Don't Want to Have Any Regrets
Kizuki finally brings to light an incident from the past that caused him to break things off with Mizuho.
20. I Don't Want to Lose You
Airu reminisces the times he had feelings for Kizuki. Syugo's family restaurant faces uncertainty.
21. The Declaration
Kizuki quits his job to pursue swimming. Meanwhile, Shin is out with a fever and Mizuho pays him a visit.
22. Something I've Been Meaning to Say
Syugo and Mizuho spend their day together in Enoshima. Will Syugo finally confess or end with regret?
23. The Proposal
Shin successfully performs surgery on Mizuho's dad. Can he finally prove to Mizuho that he can make her happy?
24. Anyway, I'm Falling in Love with You
After Shin's proposal, Mizuho makes a decision and goes to the pool to have a heart to heart with Kizuki.