Can we be sympathetic towards the Marquis?

It's difficult to have much in the way of sympathy for a murderer, especially a triple murderer like the Marquis. More to the point, it's eerily obvious that the Marquis is also a sadist—a nod to the notorious Marquis de Sade, from whose name we derive the word—a man who genuinely enjoys inflicting death and pain on the unfortunate women in his life. This is a man with an extensive collection of sadistic pornography as well as a chamber—the bloody chamber of the title—packed to the gills with diabolical instruments of torture. And if this weren't enough, the walls of his castle are bedecked by macabre paintings of dead women. The Marquis may be many things, but sympathetic he most certainly isn't.
At the same time, we don't know how the Marquis came to be this way. Perhaps he has some mental health issues of which we're unaware; perhaps there was something in his upbringing that created such an unspeakable monster. None of this would excuse his atrocious behavior in any way, but it would at least provide something by way of an explanation. Even so, neither the Marquis's background nor any potential mental health issues he might have would serve to elicit much sympathy. He is not the victim in all of this.