Many Visual Kei artists see their cross-dressing and androgyny as rooted in ancient Japanese traditions like Kabuki, not necessarily western glam rock like some sources claim. Although they started around the same time, it would be inaccurate to say that VKei is a rip-off of glam rock. There are many sub-genres of Visual Kei, including Kote-Kei, which is considered the oldest form of Visual Kei, and Angura-Kei (underground-kei), where musicians often wear Japanese Kimono or uniforms.
The term Visual Kei, originally Visual Shock Kei, comes from the X Japan slogan, Psychedelic Violence Crime of Visual Shock, seen on the cover of their 1989 album Blue Blood. The slogan is credited as coined by Seiichi Hoshiko who described Visual Kei as "The music itself along with all the visual aspects of it." He also says the slogan was inspired by X-Japan's lead guitarist, hide.
Sidenote: I just learned that the fans and their aesthetics are referred to as Bangya! Very excited to add that to my vocabulary.