“Afterthought” is an alternative rap song, describing the aftermath of a dysfunctional relationship. The lyrics reflect on where he and his partner went wrong and wonders how the partner feels about the situation.

Despite a messy break-up, Joji does not bear his ex any ill will. He only prays that both of them will find happiness and solitude, and treasure the time they had together.

New Zealand singer BENEE appears on the track for the second verse and the outro, playing as the female subject of the song.