In the winter of his first year in high school, Maru Sueharu fell in love with Kachi Shirokusa, a genius novelist who happens to be his classmate. But since it was his first love, time only continued to pass by while he could do nothing. As his so-called friend Tetsuhiko chides him and his childhood friend Shida Kuroha teases him, he overhears his crush Shirokusa saying she has a boyfriend now. His heart broken before he could even confess his feelings, Sueharu is devastated. Then Kuroha proposes that they get revenge...

Sueharu tries to dig up some bad rumors about Shirokusa's boyfriend Abe-senpai that he can use to get revenge, but it turns out Abe-senpai has been looking for Sueharu all along and knows his secret. Sueharu's desire for revenge grows even stronger when Abe-senpai reveals why he started dating Shirokusa. He decides to use his class's play production at the upcoming cultural festival as a chance to get back at him, and asks Shirokusa to write the script...

It's the day of the cultural festival. The final event of the day, the confession festival, will decide everything... Sueharu spends the day nervous as well as busy with his class's exhibit. Will the confession festival plan work out? Then a visitor comes to see Sueharu, and he realizes he's been carrying on with a massive misunderstanding. The cultural festival winds down, and with the confession festival soon to begin, Kuroha makes an unexpected move.

Sueharu thought he had carried out his plan to perfection at the confession festival, but what he thought was just a little idea of his own ended up involving everyone around him, and when he confessed to Kuroha, she rejected him. Kuroha answered his feelings with a hard no, and Shirokusa had to hear him say that he "was" in love with her, but no longer is. And now, a newcomer is about to make this love triangle even more complicated...

Kuroha's younger sisters abruptly visit Sueharu's house to tell him that she has developed amnesia. All her memories from summer break onward are gone, and they stop right when she was about to confess to Sueharu. So she suggests starting over from the moment of her own confession and erasing everything she did during the cultural festival. But Kuroha's behavior is making Shirokusa suspicious...

Sueharu couldn't suppress his rage at how he and his friends were being treated at the talent agency. They all thought his chances at getting back into show business were shot, but then Shirokusa's father presents a plan that gives him another chance. The agency and Sueharu's group will each make a commercial, and the one that gets the most votes from viewers wins. But Maria decides to work with the agency instead of Sueharu's team.

Sueharu has learned that Kuroha was lying about her amnesia. He asks her why she lied to him, but she refuses to tell him the truth. To Shirokusa, their fight just looks like flirting, and she realizes that the distance between Sueharu and Kuroha has returned to where it was before the confession festival. Unable to let the trend continue, she secretly sets a new plan in motion.

After playing throughout their first day in Okinawa, Sueharu is exhausted and falls asleep hard. When he wakes up, an angry Kuroha and her sisters stand before him! What's more, Kuroha senses that the distance between Sueharu and Shirokusa has grown smaller, so she decides to make up for the time lost due to her delayed arrival by coming on to Sueharu with all the appeal she can lay on him. Can Sueharu withstand the fierce attack of "Alter Kuroha"?!

At the end of the Okinawa trip, Sueharu was injured catching Shirokusa in a fall. So Shirokusa decides to stay at his house for a while to care for him, pleased with the chance to get ahead of the other two girls. But Shion, the maid accompanying Shirokusa, has harsh words for Sueharu with regard to his half-hearted attitude toward everyone. The next day, Maria starts attending their school, creating a harem around Sueharu that earns him the contempt of all the other boys.

Just after the group had discussed filming a documentary, the truth about Sueharu's retirement from show business is published in the weekly tabloids. Sueharu is shocked to see how dramatic and tragic the articles make his story sound. To film something that might turn this dilemma around, Shirokusa, Kuroha, and Maria take him to places where they have important memories with him, and conduct their own interviews at each location.

Shirokusa and Kuroha have agreed to appear in the drama for the true ending that's set to be released at the same time as the documentary. Kuroha, the last to interview Sueharu, looks back on her memories with him. She was there before he became an actor, the moment he became a star, and after he left show business, watching from right by his side. The place she's chosen to bring him for the interview is their "secret base," the place where they opened up to each other long ago.