Hi, I've been looking for this anime so much time that I don't really remember how long. So anime definitely aired before 2000.
It had so much erotic content, but the main plot was so great that erotic content I don't really recall. I saw only one episode at my friends. Ever since I did not see anything like that.
What I remember is that, main plot was about some cult who was sacrificing ladies, piercing trough their bodies and so on. It was so epic, I've never seen anything like that.
So main heroine, wasn't really connected with that cult, and she fall in love with some guy, and for some reason she had been attacked. But she had some magical power which protected her, and she gave her earring to her boyfriend (earring contained that power). So she fall in love and gave away her power. After a while, her boyfriend started using that power and saved her. But got into cult's hands and became a monster.
Anime had a lot of sexual content, Ecchi but not Hentai. A lot of violence, really good plot , and all that Japanese stuff, which we like.
If you've seen that, please let me know the name of anime.