Suzuki, a loner who loves BL, secretly writes a boys’ love novel inspired by Serizawa, the school’s most popular student. When Serizawa accidentally discovers his notebook, Suzuki panics, convinced he has crossed a line. To his surprise, Serizawa is not upset and even reveals that he likes BL too, offering to become the very first person to read Suzuki’s novel.

Suzuki lets Serizawa, his very first reader, read his novel and soon finds himself pulled into the bizarre “Serizawa System,” spending his lunch breaks writing right beside him. During cooking class, Serizawa’s disastrous attempt to become the “King of Simmered Dishes” adds to the chaos, while Suzuki begins to lose confidence in his ability to finish the story. As Suzuki starts to doubt himself, Serizawa offers the encouragement he needs.

Suzuki is starting to grow closer to the popular group, but he still wonders if he can truly call them friends. During a karaoke outing, an uncomfortable encounter with some old acquaintances brings his insecurities back to the surface — until Serizawa steps in to defend him.

The usually energetic Serizawa is bedridden with a fever. At school, Suzuki is caught off guard when Takeuchi asks if he has feelings for Serizawa. While trying to convince himself that Serizawa is merely his ideal model, Suzuki's feelings are put to the test when he receives an 'I want to see you' text and rushes to his side.

After dreaming that Serizawa almost kissed him, Suzuki does everything he can to deny his feelings. Troubled after finding out that a girl asked Serizawa out on a date, Suzuki struggles to write a date scene for his novel. Unable to just stand by and watch him struggle, Serizawa proposes a trip to the aquarium: "Wanna go on a date with me?"

Panicked after their kiss at the aquarium, Suzuki blurts out "Let's pretend this never happened!" and runs away. The next day, overwhelmed by pure awkwardness, things turn incredibly tense between them at school.

Flashing back to one year ago: in truth, Serizawa had fallen in love at first sight with Suzuki as he read intently in the library! Upon discovering that the book Suzuki was reading was a BL, Serizawa began secretly devouring BL novels just to get to know him better. After witnessing a former friend reject Suzuki for his passion for BL, Serizawa resolved to publicly declare his own love for BL just to protect him and become his best friend!

Agonizing over the question, "Who could Serizawa's crush actually be?!", Suzuki is spiraling. A group trip to the beach only sends his panic through the roof when upbeat, extroverted girls show up! Even after Serizawa drops an outright blatant hint—saying it's "a clueless person who is always by my side"—the hopelessly oblivious Suzuki jumps to an absurd conclusion: "It must be Takeuchi, who loves BL and has been close to him since freshman year!".

During preparations for the cultural festival, Suzuki throws himself into committee work to avoid Serizawa and bury his feelings for him. On the day of the festival, the dynamics among Suzuki and those around him begin to shift in various ways. Amid the buzz, the popular crowd decides to throw an after-party to celebrate all his hard work.

Suzuki finally finishes his BL novel and rushes to share it with Serizawa, his first reader. Moved by its happy ending and everything they've been through together, the two celebrate this special moment. Later, Suzuki gathers the courage to confess his feelings, even though he's prepared for rejection. But Serizawa's unexpected response threatens to change everything.