Hiiragi Kashima and Shizusumi "Shizu" Yagi's band "syh" is set to debut, but they run into trouble when their support guitarist leaves. Although Hiiragi often clashes with Ritsuka Uenoyama—the smug boyfriend of his childhood friend Mafuyu Satou—Hiiragi convinces him to perform as their temporary member. Despite their friction, Hiiragi acknowledges Uenoyama's talent and respects his hard work—to the point of asking him to complete an old song that Mafuyu's ex-boyfriend, Yuki Yoshida, left behind. In between writing, recording, and filming a music video, Hiiragi comes to terms with his love for the aloof Shizu and wrestles with how to convey his feelings. Meanwhile, "given"—composed of Uenoyama, Mafuyu, and their bandmates Haruki Nakayama and Akihiko Kaji—receives an offer to debut as well. The members are ready and beyond excited, save for Mafuyu, who has never before thought about playing music professionally. As Uenoyama attempts to understand Yuki and replicate his unique sound, Mafuyu steps back to ponder over the looming changes in his life, fearing what the uncertain future may bring.
