Very good story, I love it.
I am happy that you still writhe this story it's original and I enjoy this Harry.
He is tainted by darkness but no lose in the darknes, he is a grey Harry contrary to Dumbledore he had take the fight as a war ( use all mean to win and made it short for that less innocent will be caught in the fight ) and not as a fight between light and darkness ( bound be moral rule who bind his hand like Dumbledore and cause death of innocent ).
Is "friend" have been hypocrit ( they beneficit of the peace that he brought but because of how he did they had turn their back to him, and if he had fight like they "want" they will be dead with a lot of innocent ) and in this new world he can see how sad their life are without him ( too bad his Hermione, Ron and Gin can see what they will be without him in their life )
So now Harry is a little more selfish and it's good for him. I hope he will have good time with narcissa and find true friend ( go Moody ! )
I hope to see more interaction between Harry and his class, and that his little lesson can show "the light" to some persone.
Update soon : I can wait to read the next chap.
A French reader.
Merciful buckets - BJH