Grav's End Harem
Never heard of the band, but the plot synopsis is quite something...
However, I shan't be paying the £30 Amazon are asking for. I shall wait for something more reasonable.
X Japan is one of the most popular and influential bands in Japan. Their music is primarily heavy metal so it's not for everyone.
And for those who are interested I recommend checking out their 29 minute song Art of Life which has a cool 9 minute piano solo.