A j-rocker (or jrocker) is a member of a Japanese rock band. (i.e- Kyo of Dir en grey, Ken of L'Arc-en-Ciel, etc)
Some people say that Gackt is a j-rocker, yet he is not.
A J-rocker is a person who listens to Japanese Rock, it isnt very big in some countries but is huge in Germany. J-Rocker scene isnt also that big in United Kingdom there are only small minorities.
The whole J-rock/Visual Kei scene is about looking good aswell as the music. Visual Kei and J-rock are linked in with one another.
J-rockers as the minority; usually dress with extravagent hair colours and all different clothes, usually males show there feminine side.
Scott: Im a J-rocker!
John: Eh...im a emo...
J-rockers are way cooler....