For its release, B'z set out to make "May" a single that emphasized "the basics" as its theme while also being one that emitted a typical B'z atmosphere. However, upon release, fans expressed surprise, feeling that the song was a type that hadn't been on a single before, which was a reaction that Tak and Koshi did not expect. The title came from it being released in the month of May, with Tak being the one to make the suggestion. An additional reason given was the muted feeling of the lyrics being similar to "May disease"—a phenomenon in Japan used to describe the malaise and dread of returning to work and school following the April Golden Week holidays. Koshi mentioned that it was difficult to get the tone right while recording the vocals, as he did not want to stress too much emotion. One-time support member and B'z LIVE-GYM '98 "SURVIVE" keyboardist Kousuke Ooshima participated in producing the track and is credited with aiding in arrangement. The song was performed only during B'z LIVE-GYM Pleasure 2000 "juice" and was not released on home video until a single performance made its way into the premium video boxset B'z COMPLETE SINGLE BOX in 2017.