Hello Kagerou

Official music video for GReeeeN's 31st single Hello Kagerou released on February 7, 2018. A short version of the music video was posted on GReeeeN's official YouTube channel on January 11, 2018 to promote the full release as well as several campaigns, as the song itself is the official relay theme song for Fuji TV's broadcast of the 2018 Pyeongchang Olympics.

GReeeeN later uploaded the full version to their official YouTube channel on September 24, 2019, while subsequently making the short version unavailable.