每年一首的聖誕節歌曲「xmas carol」已經發行，作為2021年後的第二首聖誕節歌曲，GunChild邀請了新團隊POPIMPSTAR中的隊友KAIO進行了本次的合作，這也是GunChild加入POPIMPSTAR後的首支正式單曲。 The annual Christmas song "xmas carol" has been released. As the second Christmas song after 2021, GunChild invited KAIO from the new team POPIMPSTAR to perform this collaboration. This is also GunChild's first official single after joining POPIMPSTAR