[2] It was revealed that the EP was written and composed by Amber, including the lead single, "Shake That Brass", which features Girls' Generation member Taeyeon.

[3] In the February 12 broadcast of SBS Power FM's 'Cultwo Show', Amber revealed that she personally asked the singer if she wanted to be featured in the song.

"Beautiful" was pre-released on February 9, and also had a lyric video which contained childhood photos of Amber uploaded on S.M Entertainment's official YouTube channel on the same day.

[9] The song is an acoustic ballad, and its lyrics, written 3 years before its release, tells the story of the hardships the rapper faced as she achieved her dreams of becoming an entertainer.

[10] The last track, "I Just Wanna", is the English version of "Goodbye Summer", a song by f(x), which was included in the group's second studio album, Pink Tape.

Amber made her debut stage on Music Bank on the same day and performed two songs, "Beautiful" and "Shake That Brass" with Red Velvet's Wendy filling in for Taeyeon's parts.