The Japanese singer redirects to here: Joseph Greenwood (Joy)
There are several groups named Joy:
1) Most known "Joy" is a 80s euro disco trio from Austria.
2) Psychedelic Blues Rock band from San Diego, US. They released self-titled album in 2012.
3) French electronic music duo who are brothers, Lucas et Baptiste Malgoire.
4) A Belgian trio with Marc Huyghens
5) Belgian people (J.C. Maury , Patrick Fasseau) from Belgium in 1987, whose only production was the track "Elle et moi" (She and i) in 1987. Read more on Last.fm