Julie explained that "Kiss of Life, which is our group's name and the title of our EP, refers to the mouth-to-mouth artificial respiration method.

[1] Natty was a contestant on the South Korean reality survival shows Sixteen and Idol School, which led to the formation of Twice and Fromis 9, where she finished in 11th and 13th place respectively.

[2] Belle was known as both the daughter of Korean veteran singer Shim Shin and for taking part in composing and writing songs for several artists such as Le Sserafim, Purple Kiss, and Miyeon.

[7] Beginning with "Sugarcoat" by Natty on June 18, 2023, solo music videos of "Countdown" by Belle, "Kitty Cat" by Julie, and "Play Love Games" by Haneul were released in the following days.

"'Kiss Of Life" fulfills its function as a debut album almost perfectly with its high level of completion and clear self-introduction, paving the way for the group to move forward evenly.