Usually the professors at Hogwarts apparate or fly to Hogsmeade a day or two before term starts, but seeing as the full moon would be on September 1st that year, I was too tired to do either. Instead I was allowed to go on the train with the students, which I hoped to do inconspicuously. So I arrived early and found an empty compartment at the very end of the train. I covered myself with my cloak, and was asleep long before the train left the platform – it was the night before the full moon, after all.
I woke with a start because something felt wrong, and immediately knew why: There was a dementor on the train. I also realized that I wasn't alone in the compartment. I'd thought that no one would want to share with a sleeping stranger, but the train must have filled up. It was pitch black outside, and the lights were out, so it was difficult to make out what was happening, but I could hear worried voices all around me. As soon as I gathered my wits, I lit my wand and saw no less than 5 kids crammed into the compartment, one of which had just tried to sit on a cat.
It was in that moment that the compartment doors opened, and a dementor glided in. I immediately felt the air grow cold, and all my fears magnified a hundred times. It was clear that I wasn't the one worst off, one of the boys fainted and fell to the floor. I acted out of instinct, stepped over him and conjured a patronus – a very feeble one, given that I was having a hard time remembering anything good at the time, but it made the dementor leave non the less.
As I turned back around to face the kids in the compartment, I realized with a jolt that I knew who at least two of them were. Standing by the door, looking extremely shaken was a boy, who could only be the son of Alice and Frank Longbottom. He had his mother's round face, and even though it took some imagination at that moment, I was sure he had his father's smile. And of course, there was no mistaking the unconscious boy: He was the spitting image of James at that age.
It wasn't the way I had imagined meeting Harry: Passed out on the ground after his first encounter with a dementor. Naturally, it didn't take much to imagine what horrible moments he would have been reliving a few seconds ago, no wonder he'd collapsed. I let his friends wake him up, but made sure to hand out chocolate to everyone in the compartment, before I hurried up to see the driver and ask why he had allowed a dementor on board the train. It was also a nice excuse to get out of there and sort out the feelings that had suddenly overwhelmed me.
When told that the dementors would be guarding the gates around Hogwarts to ensure the students' safety, I knew that Dumbledore and the ministry was worried Sirius would come after Harry. It only worsened the dilemma that I'd been in ever since accepting the position. Could I be a responsible professor at Hogwarts and not tell the headmaster about the secret passages into the school? Not to mention the fact that Sirius was an Animagus. We had sworn as teenagers that no one was ever to know about Padfoot, Wormtail and Prongs, but could I keep that promise if it meant putting my students' life in danger?
I somehow managed to convince myself that it wouldn't make a difference if I told. The dementors already surrounded the castle, and Dumbledore always knew more of what was going on that he let on – surely he would know the minute Sirius chose to break in. And on that first night, I had other things on my mind. My instructions were to go immediately to the hospital wing when I arrived in the school. There I would get my first dose of Wolfsbane potion, the most wonderful invention, which would allow me to keep my mind and sanity while transformed.
On my way up to the school I managed to break up what looked like the beginning of a fight between Harry and some blonde Slytherin boy, who obviously hadn't seen me. It took me longer to get up to the hospital wing, than I'd anticipated – I'd forgotten most of the shortcuts I would have known by heart in my own school days. When I finally got there, Madam Pomfrey wasn't even there, she came in shortly afterwards, telling me that she'd had to tend to those with bad after effects of the dementors. The potion tasted horribly, but I was able to get it down by telling myself how much it would help me during the night.
In the end, I didn't get down to the feast until halfway through the sorting, but it seemed I wasn't the only one. I noticed Harry and one of the girls from the train entering right as the sorting hat was being carried out, and I also saw how many heads turned as he did. Clearly people had heard of his fainting on the train, and obviously thought he was weak, scared or childish for it. I made a mental note to explain to him at a later time how dementors pray.
Harry had barely sat down before Dumbledore got up to make his start of term speech. He explained the presence of the dementors around the school, although he was rather vague as to why they were there. Then he introduced me as the new Defence Against the Dark Arts teacher. I imagine I must have looked awful that night, right before the full moon, so I wasn't surprised that the applause was rather quiet. It did hearten me to hear it quite loudly from a spot at the Gryffindor table, where those I had met on the train were seated. It gave me hope that once the students got to know me, they wouldn't care about my shabby appearance.
Getting through the feast was tough. I was tired and irritable, and would much rather have spent the night alone, but with start of term that wasn't really an option. I left as soon as it was over, though, and headed up to my new quarters, which would be my home for the next year. When I got there, I found another goblet of Wolfsbane, which I drank immediately. I then set about unpacking my few possessions before heading down to the Shrieking Shack to transform. I figured that since it would be my first transformation with the potion, it would be best not to risk anything in case it didn't work completely.
It turned out not to be necessary, though, while my body still changed like it always had, I kept my mind and was even able to curl up and sleep for a few hours. It was a wonderful relief, and it made me very hopeful about the year to come. It felt great to be back at Hogwarts.