(やった "Hooray") is a 2001 parody song by the fictional Japanese boy band Green Leaves (はっぱ隊, Happa-tai).
[1] While the song was intended to be humorous, some viewers outside Japan assumed it to be earnest, perhaps due to the obvious work that went into the special effects in the video.
The video features the band's members singing and dancing exuberantly, most characteristically by flexing their biceps and hopping from one foot to the other, while wearing only underwear with a large green fig leaf on the front, as well as white sneakers when outdoors.
Their synchronized dancing and personalized poses for the camera parody the boy band craze of the early 2000s, while the sketch satirizes many of the stereotypes of Japanese pop culture, mainly doramas, sports TV shows and the shōjo manga aesthetic.
This includes a group shot on a street filled with floating sakura blossoms, with the band's members posing energetically towards the camera, and a brief romantic interlude during the song's bridge, where a member receives a smile from a woman passing by in the street and stares at her longingly before being comforted by his partners.