It is the second lead single for their sixth studio album The Side Effects, produced by Michael Baskette, written by Masato Hayakawa and Ryo Yokochi, and was released on 4 July 2019.

[4] The full song was officially released as a single two months later, alongside a music video, which would coincide with the significance of US Independence Day on the 4th of July.

[9] The song was written by Masato Hayakawa and Ryo Yokochi, while Michael Baskette handled the production.

From his viewpoint, the lyrics display a genuine cry of concern towards society, because he feels that "hate" and ill-will towards others has become normalised.

"[13]The music video for "Coexist" was released alongside the single on July 4, 2019, and was directed by Takuya Oyama.

[14] The music video is played within a futuristic-styled background, implied to be set inside of a UFO and revolves around a romantic couple who both get individually abducted by a blue-looking alien.

They spend 7 days isolated and studied by the alien, who eventually allows them to reunite and leave the ship after finding an error in the system.