The central mystery of "given" is the story behind Mafuyu's silence and the Gibson guitar he carries. The major reveal, culminating in Episode 9, is that the guitar belonged to his childhood best friend and boyfriend, Yuki Yoshida, who died by suicide. The two had a fight, born from the pressures of their bands heading in different directions, during which a frustrated Mafuyu asked, "Are you willing to die for me, then?" These were the last words he ever spoke to Yuki, leaving him with an unbearable burden of guilt that rendered him emotionally paralyzed. Music, and specifically Ritsuka's help, becomes the only way for him to break his silence.
The climax of the series is the band's first live show, where Mafuyu, who hadn't written any lyrics, spontaneously pours his entire story into the song "Fuyu no Hanashi" ("A Winter Story"). The lyrics serve as the final, unsent letter to Yuki, expressing his loneliness, his lingering love, and his journey toward finding a new future. It's a moment of profound catharsis that finally allows him to cry. Immediately after the performance, an overwhelmed Ritsuka kisses Mafuyu backstage, solidifying their romantic feelings. In the final episode, Mafuyu officially confesses to Ritsuka, and the band names themselves "Given," acknowledging the gift of music and relationships that grew from Yuki's legacy. The ending shows Mafuyu telling his childhood friend Hiiragi that he has found someone new to love, signifying that he has fully accepted his past and is ready to move forward with Ritsuka.