Disclaimer: I do not own Harry Potter.
Dumbledore managed to sweep things under the rug, but it cost him the ability to take down Fudge. By sweeping away the events in that courtroom, he swept away the obvious injustice of it as well, and used considerable favours to do so.
Gaining the full magical power of those souls did not go unnoticed however, and Dumbledore could not or would not sweep the rest away. He probably figured like Fudge did that I would become what was inside me. He did manage to keep me from getting executed by a dementor however. Assuming one would go near me. I've been in Azkaban for a while now and haven't even felt a chill. That could be from my impressively glowing aura of limitless magical power though. Just a hunch.
Officials have come to transfer me to my 'appeal', but I know what they're really trying to do. Get me in through the Veil of Death. The thing about having all these souls in me. I got their knowledge too. It wasn't instant. Being in here have me plenty of time to search through those memories though, and learn what I needed. Now I can read surface thoughts through eye contact. Now that's a useful skill. I also learned about animagus transformations. And is mine ever a doozy. Having all these wizards and their dark magic in me, along with a Basalisk's venom and Phoenix's tears has given my animagus some unique characteristics.
After all, what animal could possibly hold all of this power, and have a connection to both those magical creatures? Boy were they surprised when I grew to smash through the walls of my cell and started breathing fire back into the hole I made. I wonder if they burned away with the magic resistant stone or not.
I guess they ordered the Dementers to stop me because a large flock of them soon surrounded me as I perched on the old fortress. One came a little too close and my hatred for them along with my new instincts and dark power caused me to snap. Not mentally, at least I don't think so. Crazy people don't know they're crazy though do they.
I snapped my large jaw around the first Dementer to come close enough and swallowed it whole. I felt a rush of power from the souls within it join my collection somehow. I growled more than grinned then. The Dementers did try to flee after my second bite. But floating capes really don't compete with a dragon's wings. I chased those evil little snacks around the fortress and surrounding waters for a few hours before I finished gobbling them all up.
I spent the rest of the day on my back laying on the rocky with my bloated belly sticking up, being lulled to sleep by the crashing waves. Who knew Dementers were so filling? I had some souls to sort through and decided to take a nap, confident that I was in no danger. Ever again.
