[1] On April 20, the track listing was released with "Heya" and "Accendio" announced as the lead singles.
[6] "Heya" was written by Lee Seu-ran, Exy, and Sohlhee, composed and arranged by Ryan S. Jhun, Dem Jointz, Jack Brady and Jordan Roman of The Wavys, and Ido Nadjar, with Kloe Latimer participating in the composition.
[7] Described as a hip hop song with lyrics about "folk tale",[8] "Heya" was composed in the key of F minor, with a tempo of 92 beats per minute.
[20] On the Oricon Combined Singles, the song debuted at number 13 in the chart issue dated May 13, 2024.
[22] In Malaysia, the song debuted at number 14 on the RIM Top 20 Most Streamed International in the chart issue dated May 3–9, 2024.
[28] In New Zealand, the song debuted at number 30 on the RMNZ Hot Singles on the chart dated May 6, 2024.