Thanks for the info and the links. I don't think I've been to this site before.
There is also this website which is not bad:
https://idol.ne.jp/hayakawamegumi
I was wondering why Megumi Hayakawa's career had ended so suddenly, so it would be simply the producers' fault... However she must have been successful, 6 albums and 4 singles at not even a year and a half, it’s huge... So I said to myself that she could not stand the pressure or that she was fed up with the scene… Anyway, it's a shame to have stopped so quickly, even if there are a lot of songs to listen and listen again…
In fact more than metal idols, it's mostly great and strong voices that I'm looking for, so it can be singers within bands too.
I also know a little Youri Sugimoto, especially through her songs for animes. She has a great voice, I love especially her songs for the OVA "Digital Devil Story: Megami Taisen" and the movie "Grey Digital Target".
On the other hand I find her 1984 album "Dynamyte" a little disappointing compared to his good reputation on the web. Even if there are 3 or 4 songs not bad, the melodies are not very catchy and lack originality mostly, and the instrumentations lack a bit of madness.
That said, speaking of this album, I can add it to VGMdb, since we find Masatoshi Nishimura there…