The meme stems from NSYNC's 2000 smash hit "It's Gonna Be Me." When singing the titular line in the song, Timberlake annunciates the word "me" as "May." According to a 2016 article from E!

The meme stems from a line sung by Justin Timberlake in the 2000 *NSYNC hit “It’s Gonna Be Me,” where his pronunciation famously sounds like “May.” Each year, fans get more creative with ...

The "It's Gonna Be May" meme, originating from a 2000 NSYNC song ... Sings lead vocalist Timberlake: "Baby, when you finally get to love somebody, guess what — it's gonna be meee." ...