Boku Nanka

[1] Nao Kosaka was appointed as center (lead performer) of the title track for the fifth time after the fourth single "Sonna Koto Nai yo" in 2020.

[4] During production, she had just recently returned from health leave and did not participate in the more intense dance scenes in the music video for "Koishita Sakana wa Sora o Tobu".

She served as center for the second generation members' B-side song "Koishita Sakana wa Sora wo Tobu",[a][2] and the music video for "Hikōkigumo ga Dekiru Riyū"[b] is about the closing of a dormitory named "Hidamari", a reference to her 2019 photobook of the same title.

[9] Real Sound commented that the rock ballad sound of "Boku Nanka" reflects the growth of the group, especially after experiencing different lead performers in the previous two singles, while the melody represents Kosaka's "ephemeral, fragile radiance" as she returned from her hiatus.

[11] "Koishita Sakana wa Sora wo Tobu" was also said to fit Watanabe, who enjoys both rock music and defying conventions, and is reminiscent of the group's origins as the subgroup of Keyakizaka46, who were known for their "cool" songs; on the other hand, "Hikōkigumo ga Dekiru Riyū" with its retro-style music video represents "nostalgia" and the happy memories created by Watanabe and the other members over the years.

Costume for "Mayonaka no Zange Taikai"