Lyrics and composition
Within the narrative of KPop Demon Hunters, "Golden" is the latest musical release by Huntrix, intended to bring about the "Golden Honmoon", a permanent magical barrier against the demons that Huntrix fight. As the song plays in the film, the audience learns that Rumi is secretly half-demon. Ian Eisendrath, executive producer for the soundtrack album, described "Golden" as an "I Want" song that explores the characters' purpose while also dwelling on Rumi's inner thoughts during the song's bridge, which shifts from "inspirational pop" to a slightly darker "sotto voce". The Chosun Daily wrote that "while over 90% of the lyrics are in English, key moments feature Korean words such as 'eoduwajin' ('darkened') and 'yeongwonhi ggaejil su eomneun' ('unbreakable forever'), preserving its K-pop identity".
Eisendrath said that they initially "had five to six songs written for that slot" but kept developing "until it was the right energy. The directors are tough customers, in the best possible way, and they had a real vision for what this needed to be". The song had the working title "Gold" during production. According to Danny Chung, who worked and performed on the film's soundtrack, "Golden" was "the last [song] to be really locked in". It went "through a few iterations of production, meaning the instrumental changed a few times before it landed where it would be." The song was co-written by Ejae and Mark Sonnenblick "under the guidance" of Eisendrath.
The song is performed in G major, covering a three-octave range up to a high A at A5. Music critic Lim Hee-yoon's wrote that "the powerful high note reaching up to a high A in the third octave is rarely used in idol songs", adding "freshness". Ars Technica wrote that the song's three-octave range was "impressive", saying A5 was "usually reserved for classically trained operatic sopranos". Ejae told Korea JoongAng Daily that she "intentionally wrote a challenging vocal line" to "reflect both Rumi's vocal prowess and her fierce determination to seal the magical barrier of [the] Honmoon", and said that she "just followed where the melody took me, and suddenly I was hitting an A5 note". Co-director Maggie Kang said that they "had Ejae sing the highest notes that she could possibly sing in a lot of the songs," including "Golden". The Washington Post wrote that "it was important to Kang that the song embody 'the feeling that you get when you hear an artist, like, just put all of her talent and effort and that physical struggle into hitting a note'".
Co-director Chris Appelhans said the "I Want" song followed "the conventions of a traditional musical" while also "making it a legitimately great pop song" which "is probably why it's [in the Top 10] on the worldwide Spotify charts", adding that "a good pop song also tells a story" which is what "Golden" is doing. In a Reddit "Ask Me Anything" interview, Appelhans said "Golden" was inspired by songs such as Biggie's "Juicy" and "Forever" by Drake, Kanye West, Lil Wayne, and Eminem that helped the writers "understand how a pop song could be a biography about starting as a nobody and finding yourself".