Wakana Gojo (Kouta Nomura), an aspiring Hina doll craftsman, struggles to connect with his classmates due to his singular devotion to his craft. One day, when his sewing machine breaks, he decides to borrow the one in the school’s home economics room early in the morning, hoping to work unnoticed. However, Marin Kitagawa (Riko Nagase), a bright and outgoing classmate from a seemingly different world, unexpectedly walks in. Caught making doll clothes, Wakana panics and accidentally drops his Hina doll. Overwhelmed by past trauma, he quickly tries to hide it, only for Marin to surprise him with her genuine praise. Breaking Wakana’s expectations, Marin then asks him for help with something that only someone skilled in sewing like him could handle, setting their story in motion.

Wakana Gojo (Kouta Nomura), tasked with creating a cosplay outfit for Marin Kitagawa (Riko Nagase), is stunned that someone so different from him would want to connect. Marin surprises him further by suddenly visiting his house, saying she couldn’t wait for measurements and tracked down his address. After taking her measurements, Wakana struggles at school, where Marin casually approaches him despite judgmental stares. Trying to avoid attention, Wakana distances himself, but Marin confronts him, confused why a friend would avoid her. Moved by her words, Wakana resolves to create Marin’s costume and shares his dream of becoming a Hina doll craftsman, deepening their bond. However, he learns Marin plans to wear the outfit at a cosplay event in just two weeks. Determined to meet the deadline, Wakana throws himself into the project.

Wakana Gojo (Kouta Nomura) faces mounting pressure as he juggles school, family responsibilities, and an important project for Marin Kitagawa (Riko Nagase). With a looming deadline, Wakana finds himself struggling to balance everything, questioning his own abilities as the challenges pile up. Meanwhile, Marin’s enthusiasm for the project remains unwavering, her excitement pushing Wakana to keep moving forward despite his doubts. As time ticks down, Wakana must find the strength to persevere, driven by his desire to succeed and to bring a smile to Marin’s face.

After completing the cosplay outfit for Shizuku-tan, Wakana Gojo (Kouta Nomura) reflects on how much his time with Marin Kitagawa (Riko Nagase) has meant to him, unsure of what comes next. Marin, however, surprises him by sharing ideas for her next cosplay. Wakana, who thought their collaboration was a one-time thing, is caught off guard but happy at the thought of continuing to work together. Not long after, Wakana receives an unexpected visit from Sajuna Inui (Akina Ikeda), a well-known cosplayer. She’s impressed by recent work she’s seen and asks for help with a new project. When Marin joins the meeting, her excitement about working with Sajuna further motivates Wakana. With this new challenge ahead, Wakana is ready to take the next step in his journey, inspired by those around him.

One day, career planning forms are handed out at school, prompting Wakana Gojo (Kouta Nomura) to discuss his future with Marin Kitagawa (Riko Nagase). Struggling to decide, Wakana submits his form marked as undecided. Meanwhile, Marin, Wakana, Sajuna Inui (Akina Ikeda), and her sister Shinju (Kokoro Toyoshima) visit an abandoned building to scout it as a location for their upcoming cosplay shoot, "Reketsu!! Awasé." During the visit, Wakana learns more about Sajuna’s passion for cosplay. Later, while working on costumes at Wakana's house, Marin suggests that Shinju might secretly want to cosplay herself. Wakana, who has always found it difficult to share his own interests, empathizes with Shinju’s hesitation. However, Marin’s encouragement to embrace what you love inspires Wakana to come up with an idea. On the day of the "Reketsu!! Awasé" shoot, Shinju arrives late, surprising everyone as she reveals her own cosplay, stepping forward with newfound confidence.

During summer break, Wakana Gojo (Kouta Nomura) focuses on his Hina doll crafting training, while Marin Kitagawa (Riko Nagase) keeps busy with her part-time job to avoid disturbing him. Marin’s growing feelings for Wakana remain unnoticed as he struggles with his training, feeling mentally drained. Hoping to cheer him up, Marin invites Wakana on a shopping trip. During their outing, Wakana decides to create a cosplay outfit for Marin’s favorite character, "Liz-kun," reigniting his passion for costume-making. They plan the fitting at Marin’s house, where Wakana feels nervous visiting for the first time. Excited by the fitting, the two get carried away and hold an impromptu photoshoot. Caught up in the moment, they find themselves unexpectedly close when Marin’s father suddenly returns home, catching them off guard.

Although Marin Kitagawa's (Riko Nagase) father clears up his misunderstanding, he bans her from cosplaying until she finishes her summer homework. Unable to see Wakana Gojo (Kouta Nomura) as often, Marin shares her romantic worries with Sajuna (Akina Ikeda) and Shinju Inui (Kokoro Toyoshima), who encourage her to confess her feelings. Determined, Marin decides to tell Wakana how she feels after summer break. Once school resumes, Wakana and Marin begin work on a new cosplay outfit. However, a third-year student, Amano (Taichi Shiozaki), spots them working together and realizes Wakana is making costumes. When Amano approaches Wakana with questions about cosplay, Wakana avoids answering and quickly leaves. Later that weekend, Marin and Wakana attend a cosplay event together, only to encounter Amano, who surprises them by appearing in a stunning crossplay outfit.

Marin Kitagawa (Riko Nagase) struggles with growing feelings for Wakana Gojo (Kouta Nomura) and decides to focus on her class’s cultural festival costume contest. Determined to protect Wakana’s secret talent, Marin resolves to make the cosplay outfit herself instead of asking for his help. Despite support from classmates, Marin’s inexperience makes the project overwhelming, affecting her health. Wakana, noticing her struggles, becomes concerned but hesitates to intervene. Inspired by Marin’s dedication, he makes a bold decision during homeroom, surprising everyone and offering a solution to help the class succeed.

Wakana Gojo (Kouta Nomura) publicly reveals that he has been making Marin Kitagawa’s (Riko Nagase) cosplay outfit. Though surprised, his classmates are supportive, ensuring he can focus on the project. Seeing their positive reactions, Wakana begins to realize he may have underestimated their acceptance all along. Meanwhile, Marin resolves to confess her feelings to Wakana if they win first place in the costume contest. On the day of the cultural festival, Marin gives Wakana a samue outfit as a thank-you gift, purchased with her part-time earnings. With the contest’s outcome crucial to the class’s victory, Wakana begins applying Marin’s makeup. However, as curious classmates gather to watch, the mounting pressure unsettles him, testing his ability to stay focused under so many watchful eyes.

Overwhelmed by pressure, Wakana Gojo (Kouta Nomura) steps outside to calm himself and unexpectedly encounters Sajuna Inui (Akina Ikeda), who is visiting the cultural festival. Noticing his samue, Sajuna guesses it was a gift from Marin Kitagawa (Riko Nagase). When Wakana asks how she knew, Sajuna points to the sleeve, where his name, "Wakana Gojo," is clumsily embroidered. She remarks, "You wanted to do it yourself, didn’t you?" Seeing the imperfect stitches, Wakana recalls his memories with Marin and realizes how much her support has meant to him. Renewed with determination, he vows to help Marin win first place. Returning to the classroom, Wakana resumes Marin’s makeup with a focused resolve. The classmates quietly leave, sensing the pair’s serious energy. Finally, the long-awaited costume contest begins, and when Marin steps onto the stage, the audience’s reaction is nothing short of electric.