Webakaza being turned into a demon didn’t change who he was, it twisted him:
His ideals, his morals, his and motivation for seeking power were corrupted by muzan.
And in spite of.
Webin this post, i'll use akaza as an example.
How demon slayer absolves akaza of his crimes.
Have other characters tell him how good of a person he still is, in spite of him.
Webbecoming a demon doesn't change who he is, it twists him:
His ideals, his morals, his purpose for seeking physical strength at all.
And when he is so strong that none of that.