Dear Professor Snape:
I am writing to all my teachers to say farewell now that I am graduating from Hogwarts. At first I wasn't sure you would appreciate receiving a letter from me, but I decided that if you've already read this far, I should at least attempt to write to you as well.
I know we haven't been the best of friends these past seven years, and first and foremost, I would like to apologize for viewing your most private memory in the pensieve two years ago. It was a terrible, inappropriate thing for me to do, but it made me realize that my father was not the saint I once thought him to be. Of course this is obvious to you. I regret any insult I may have given you by assuming my father innocent of all faults.
You have every right to hate my father and the Marauders, but now I must ask you to do something that I think is very important: please understand that I am not my father, that it is not my fault I was born to him, and that I did not ask to grow up famous. I realize that we can never be friends, but as I leave Hogwarts, I hope that we can come to a mutual respect as human beings. I don't want my memories of Hogwarts to be peppered with hate for you, because I know you have done loyal work for the Order and the side of light, and that you are a great wizard. Even though there was bad blood between us from the first day I sat in your potions class, I would not like to leave the school without attempting to patch our relationship slightly.
I am not writing this as a self-righteous attempt to feel better about myself as a person, as you will most likely assume. It is simply a sincere offering of peace—mutual respect, if you will not take anything more. I hope that if we meet in the future, we will be able to put aside our differences and understand that there are many things in this world much more important due to their danger than a vindictive grudge between two people. The past several years' events should have taught that to all of us.
Sincerely,
Harry Potter
Severus Snape read the letter with curiosity. Had Harry said it to his face, he would have retaliated with all the venom he had shown the boy—man—in the last seven years, but alone in his office, he had the freedom to consider it without having to live up to his reputation.
It seemed genuine enough, or as genuine as a large-headed Gryffindor hero could manage.
"'Not the best of friends,' indeed," he muttered. "It was just a passing 'my teacher gave me bad marks' grudge, I suppose. Really, Potter, and don't go lecturing me on what the last several years should have taught me."
Still, Severus picked up a quill. Sucking on a blood-flavored lollipop to improve his mood, he wrote:
Dear Potter Boy:
No. He magically erased that. It was too silly. He began again.
Dear Mr. Potter:
My congratulations on your upcoming graduation from Hogwarts, and for your recent defeat of the Dark Lord.
Severus pulled back his sleeve to look at the healing wound on his forearm where the Dark Mark had blasted itself apart upon Voldemort's death.
No doubt you are eager to leave my classroom forever. Five points to Gryffindor for the fact that you had the consideration to write to your Potions professor, and fifteen away from Gryffindor for the letter's contents. You are an incurably insolent young man to think that I would be moved by that sappy drivel.
It has come by me that you will be beginning a career as an auror, and I have only one piece of advice for you, not that you will bother to take it. Never become a teacher. Children are a maddening rabble and drain one's energies with unnatural rapidity.
In all honesty, he couldn't stand the thought of Harry Potter landing the position he had always coveted: Defense Against the Dark Arts. Even though it would most likely mean the man's early demise, the thought of Harry taking that professorship before him made him seethe with rage.
As for this "our relationship" business, I assure you I wish we had never had the chance to develop one of any value. Please do not attempt any more "relationship-building" with me in the future.
Your Late Potions Master
Snape almost summoned an owl but stopped at the last second. He contemplated Harry's letter again, and then looked at his own. He crumpled both up and threw them in the waste paper basket. In this case, no response would be the most considerate. Remember the golden rule…