"Me ga Aku Aiiro", a complicated seven-minute rock opera, had been the final song that the band worked on for Kikuuiki, with recording sessions lasting until February 16, a month before the album's release. After the success of Kikuuiki, they felt that the time was opportune for the band to quickly release new material. This time also coincided with the time when band members began to smoothly and enjoyably record music together, compared to the band's earlier albums, such as Night Fishing (2008), where the process was difficult and frustrating. After the band's success with "Aruku Around" and Kikuuiki, "Identity" was the first song the band wrote specifically for a wider audience. The song's lyrics were directly inspired by "Me ga Aku Aiiro", which were written after "Me ga Aku Aiiro" had been completed. For "Me ga Aku Aiiro", Yamaguchi felt that he needed to develop a new style of lyric writing for himself, featuring abstract concepts but words that people would still empathise with. The first part of the song was inspired by an incident where Yamaguchi was watching people carry out their daily lives. He noticed that almost all of the women around him were wearing leggings, which made him hyper-sensitive to each person's individuality. This feeling, which had been unconscious for him before, inspired the song's chorus lyric and melody. The rest of the lyrics were inspired by YouTube comments, which Yamaguchi noticed were often further comments of already existing comments, instead of a comment about their first impressions of the video. This made him realise that people often base their identities on the actions of other people. After considering the idea, Yamaguchi considered the only time people were free from these outside influences were in early childhood, where people's actions were expressing their pure self-identity, and wanted to express his conclusion in the lyrics of "Identity". The song's final lyrics were written by Yamaguchi in three perspectives: the perspective of someone on stage, an audience member perspective and a third perspective encompassing both aspects. The song was given the concept of a Sakanaction version of Southern All Stars' 1978 song "Katte ni Sinbad" when writing. While Yamaguchi said this as a joke, he felt that this was true for where the band were in their career (like Southern All Stars, who were able to produce many high response singles after "Katte ni Sinbad", such as "Itoshi