Alastor isn't just seeking power for the sake of power. He doesn't want to be treated the way he was when he was alive. To be looked down on by white people who think they're superior just because of the color of their skin or their upbringing.
He secured his place in hell as the most powerful sinner so that nobody would dare disrespect him ever again. Alastor may have loved his life and he had his dream job but he lived in a time where racism was the norm. He had to work his ass off for everything in his life and just to have even the smallest bit of respect.








