A dance-pop track with influence from dubstep genre, the song was written by songwriter Kenzie, while production was handled by Yaakov 'Yash' Gruzman, Jenson Vaughn, Delaney Jane and Yoo Young-jin.
Rania Aniftos of Billboard magazine described the track as "bold", further praising Irene and Seulgi for "preaching their confident individuality, and the "monster" inside as they deliver sultry choreography weaved in with eerie, paranormal scenery.".
[16] Writer Riddhi Chakraborty of Rolling Stone India described the song as "one of the most stand-out singles of the year" referring to the subunit's "fascinating use of dark pop and dubstep".
[17] On another song review, writers Kim Sung-hwan, Yeol Shim-hi, Yoo Seong-eun, and Cha Yoo-jung of Y-Magazine described the track as "well-organized, from narratives reminiscent of delicate horror movies", further adding the "style with the energy of thought in the midst of mystery by utilizing its bold movements and images of femme fatale", while rating the track with three point five stars out of five.
[18] In an individual album review, Kim Do-heon of IZM viewed the track as "a neat composition without superfluousness" adding that "there is a lack of element that can be imprinted".
[19] Buzzfeed ranked the song number 30 on their list, citing it as "delightfully scary as they detail possessing someone and toying with them as they struggle to break free from their hold".