Pluto in the 8th House is by essence the most Plutonian of all Pluto placements. It's also the most "comfortable" in the sense that Pluto is operating where it belongs: In the shadows.
When Pluto is located in the 8th house, there is a strong urge to discover, name, face, and defeat your personal demons. The obsessive and compulsive quality of Pluto is directed towards one's personal shadow. If you're not so much Plutonian you probably wonder what a shadow is, but if you're a 8th houser and especially if you have Pluto there, chances are, you have a strong awareness of what we're talking about.
Pluto represents darkness, and as the saying goes: you need to be bringing light to the darkness, in order to transmute it. This is what someone with Pluto in the 8th house is aiming to do, slaying their demons.
Now it would be all fun and game if it was that straightforward, but Pluto is anything but. Pluto represents compulsion and repulsion, a compulsive desire to face the dark and the unknown yet a repulsion in doing so. Pluto is always simultaneously possessed by a desire and repulsed by it, because it knows very well the danger that lies in what it desires. Ever heard of Plutonian relationships? That's what they're all about.
When Pluto is located in your 8th house, you're constantly feeling the pull of your own darkness, calling for you to face it. Will you be up to the challenge, or will you bury it as deep as you can and never look back?
With Pluto it's always the same dance - ignore it and let it control you, face it and learn how to control it. There is no other option, besides looking the other way and suffering for no other reason than falling for paralysis.
Because the 8th house rules intimate relationships, often the person learns how to face their personal demons through intimate relationships. But here's the thing, if someone falls victim of the "bury and be controlled by", this will show up in the relationship. Typically, it will give relationships which could have been incredibly transformative and empowering, but turn out to be a constant power struggle, tug of war, and a place where little intimacy is achieved (because if it WAS achieved, then the facing of demons would occur). Another option can be someone who remains unattached, uncommitted, another way of avoiding the scary confrontation with oneself.
The dance of Pluto remains the same always, the more you resist its call the more you suffer. The call simply never stops, and with Pluto in the 8th house, the lesson is this one: You have to accept your darkness and your capacity to be a dangerous person. Your personal power is drawn from facing your darkness, acknowledging it, and once integrated, making a conscious choice not to choose it.
Personal readings available
"Pluto an evolutionary journey of the soul": By Jeff Green
"The book of Pluto": Steven Forrest