The EP consists of five tracks and incorporates Pop, R&B and Hip hop music genres.

[3][4] On August 13, "Because I'm the Best" (or "Roll Deep" in international markets) featuring Jung Ilhoon of BtoB was announced as the album's title track.

[18] Billboard contributor Jeff Benjamin praised "Because I'm The Best", saying "HyunA confidently raps and chants about her swag, making playful remarks about how even her friends are jealous of her because, well, she's the best.

Ilhoon [...] drops in to further the claims as the two spit over hard-hitting, synth-heavy hip-hop production with elements recalling recent work from Mike Will Made It and DJ Mustard."

Benjamin also highlighted the styling and aesthetic of the track's music video, citing its "tongue-in-cheek presentation" as proof of the opinion that "HyunA is easily one of the baddest females in K-pop.