Third years

"Good morning, class."

He hoped he sounded calm. He hoped he sounded like a teacher. He hoped he sounded like a sane, reliable person, someone who would, in time, take the role of a deceased father.

Sirius Black looked at the class of third-years, and his silvery blue gaze met a pair of bright green eyes. Eyes so much like Lily's, on a face that looked like James in the rare moments when he wasn't plotting something wild and adventurous.

He had seen this boy during practice last night. Remus had taken him directly to the quidditch pitch after dinner, an hour before moonrise. He had introduced the substitute teacher to the Gryffindor team, then had hurried back to the castle to take his potion. After training, which Sirius could watch from the referee's tower, they had their first talk – mostly about James and quidditch in general. The team captain (his name was something tree-related, but Sirius couldn't for his life remember what it was) mentioned the interview in the Prophet.

"No wonder he was the youngest seeker Gryffindor ever had," a pretty chaser witch added. "With a godfather who'd give him a broom when he was only one!"

They all laughed. Harry's green eyes were shining as he looked at his godfather, and he asked if Sirius could share more stories about James the next day.

It was a good start, in short. Sirius was greeted as a long-lost family member, not as a walking ghost who should have been staying at St. Mungo's, sipping recovery potion. After long years, he could hope for a normal life again.

But teaching was different. He had to prove himself: to the Gryffindors, to the Slytherins, and also, to himself. Not even those green-robed little purebloods doubted him as much as he doubted himself. Teaching wasn't even his idea, to come and try his hand at the position that had been jinxed before he was born. However, Lupin had asked him, if only to prevent a second catastrophe after Snape had talked about werewolves in his absence.

"Good morning, Professor Black," chorused the students.

Sirius touched his wand for reassurance. He felt like a fish out of water. "As you all know, Remus is unable to teach today. I will leave teaching about imps to him when he gets better. But if anyone is curious," he blinked at the long-haired witch he had met in the library the previous day, "she can read the book, of course."

"Not werewolves again," another Gryffindor witch, a brown-skinned young lady, murmured. He replied with a wide grin.

"What I'm about to teach you today is not in the books, not this one, nor any in the front half of Madam Pince's domain." Suddenly, the students appeared intrigued. "It won't be in your exams, now or during your N.E.W.T.s and I doubt it will ever earn your houses any points." The bookworm witch now looked disappointed while every other kid was staring at him in anticipation. Harry wiped his unruly hair from his forehead, revealing the lightning scar.

"Only, it might save your lives, more than once if you have any enemies. Not a powerful defence, but you will at least know who to be prepared for." He wished he could remember all the mischief the Marauders had once managed, but his memories had faded too much in the past several years.

"I believe you were told to bring two rolls of parchment. One is what you will write on. Now, please, cut the other in half. You can keep the notes, but these halves will be incinerated before the lesson is over. Ready? Now, we will start with a signature spell. Point your wands at the centre of the parchment, and focus on how you would define yourself. Try not to lie to your own wands."

He gave them a few moments to gather their thoughts.

"Now, the incantation is extremely complicated. After the wand makes contact, say this." He paused, his mischievous smile back. "I."

All right, it wasn't the best joke he ever had, but it was someplace to start.

"My name appeared there!"

"Mine too!"

"That's better than my real handwriting!"

"I take it that you haven't learnt the signature spell yet. Be warned, its use is taken seriously. Also, it is extremely hard to forge, because there are subtle differences between a real signature and one that's copied with a quill. Also, a wizard might be able to reproduce another's signature, if they have permission. However, once the signature is permitted, the wizard can reproduce it anytime with the same spell. An untrained eye can skip the markers this kind of secondary signature leaves, and some say it's better quality if the wand is either the same as the first time, or if it's the signatured wizard's own. In Gringotts, for example, this is one of the reasons the wand is observed." He waited for the students to take notes. Very few did.

"Now, on to being prepared for an attack. I would like you to point your wands at the person next to you, hold the same parchment in your other hand, then wave the wand's tip to the sheet. Try it."

It still wasn't N.E.W.T.-level enchantment, but the pupils had apparently never tried it before. They all were surprised when the other's name appeared on the parchment next to their own.

"I'd rather have werewolves again," a Slytherin yawned. Sirius ignored him.

"Now, please, take your quills and draw the outlines of this room. Then stand up and get the others' names on your sheets. Get as many as you can - you have one minute."

The children started moving, and so did the names on their parchments. Soon, everybody had the map of the classroom, and had at least twelve names scattered across it. Each student was holding a sheet with themselves in the middle, and they could easily tell who was behind them, or who was in the opposite corner, out of their sight.

"Good! Time's up! Am I still as boring as Snivellus Snape?"

"Worse!" a Slytherin girl immediately replied. She sounded more sullen than bored. Apparently she understood that this mapping spell could ruin the sort of entertainment she preferred. Sirius ignored her.

"Return to your seats, please. Take notes, because those are what you will take home from class today." With that, he collected all the used parchments from their desks, made a ball of them in the centre, then set it alight. He ignored the protests.

"Now, let's go to the corridor with the other half of your parchments, take your ink and quill, and ten points to whoever finds Mr. Filch first. Twenty points if you manage in the first two minutes, thirty if you make it one. Time starts... Now!"

He watched as the kids spread out to the stairway, where they started waving their wands at random directions. Some started with charting the castle. Soon they had rudimentary maps of the building, with various people of various classrooms being tracked on them. Sirius looked at them with pride. One hour into his teaching, and he had already managed to pass on the most important self-protecting art of magic that he had learnt during his school years.

"Sir?"

Harry was hanging back with him, not even trying to find Filch.

"May I ask you something, Mr. Black?"

"Anything, kid." He looked at his godson, afraid that he'd be asked if he had James Potter's permission to use his signature. He didn't have an idea what to reply in that case. As he remembered, Harry's permission form to Hogsmeade had been signed on an icy July night. Anyone with eyes could tell it was an allowed replication of his father's writing. In fact, someone without eyes had been quite upset afterwards, thinking Sirius's visit would be discovered. He had no idea what to say when James's son would ask how he slipped from Azkaban to visit him before his birthday. He would lie to the Department of Magical Law Enforcement, but not to Harry.

"Have you ever sworn, sir, that you're up to no good?"

Sirius's jaw dropped. The question explained why Harry didn't find the search for Filch any bit challenging.

"You have the map," he whispered. "Our map? The Marauders' Map?"

In reply, the boy took out the old parchment from his pocket. "I got it from two fifth years," he admitted, but didn't say more.

"Can I... Can I tell it just one thing?" Sirius begged. Harry, still hesitantly as if he somehow feared the map, gave it to him.

The substitute teacher unfolded it as if the old sheet were the most precious treasure in the wizarding world. Without activating the map, he touched his wand to the parchment and said, "I'm back from Azkaban."

Much like when an unworthy would try to operate it, the map wrote back to him. Four lines appeared, one after the other.

'I hope, at least, you made a glorious escape? Swimming to the shore on your own, or something similar?'

This was his own handwriting. Sirius would have hated to disappoint his own past self. Being released was a common and traditional way, compared to an unaided escape that had never happened before.

'Good to hear! I told you you'd end up there!'

This was written in small, uneven letters. Sirius ignored it.

'Welcome home.'

The wizard smiled at Moony's words. In fact, Remus's current self was still exactly as quiet and gentle as he had always been. But the substitute teacher was waiting for the last line, written by the memory of a friend who had died long ago.

'Too bad. We agreed we'd go there together.'

And wouldn't have that been more bearable, Sirius grinned. He wiped a tear from his eye, and gave the map back to Harry. The green-eyed boy seemed even more suspicious about the parchment now.

"Last year, I happened across a diary that kept writing back in a similar way."

Sirius nodded. After the full moon of September Moony had sent him a letter in which he'd mentioned the latest dark lord's horcrux diary. He was quick to assure Harry that the Marauders' Map wasn't anything like that.

"We spent so much time with it, our map became something like a portrait of the four of us. It works on the same principles. Here, take it back. You inherited it, after all. And thank you."

"I... Inherited?"

"Since Prongs has died, it's only fair it would be passed on to his son." Harry's eyes grew wider. "We lost this in seventh year. It was confiscated, and before we could have taken it back, we graduated, and went our merry ways to auror training. Moony planned to get it back someday, but Prongs convinced him that the map would be earned by someone worthy of it." Sirius looked into those green eyes, now full with awe. "And wasn't your father right? Here, take it. And go, don't just use it, but make sure you learn to make a better version."

"Thank you, sir," Harry managed. He folded the map back, and put it into the inner pocket, close to his heart.

Sirius went to check on the other students. Some had formed groups, each member trying to find the caretaker in one specific place or the other. And they had interesting results.

"Uhm, I think I have Peeves on my map," somebody said. "Doesn't he count as something worse than Filch?"

"Can't I get a point for finding the Bloody Baron?"

"How can Hermione be on the second floor? What's that - arithmancy class?"

"I FOUND HIM!"

A blond Slytherin boy ran to the substitute teacher, proudly showing his map, on which Argus Filch was approaching.

"Children out of the room during class!" Now they could hear him, as well. Perhaps the old squib found the kids faster than the other way around. Sirius suppressed an uncomfortable thought that the man wasn't without magic at all; only, he possessed it for the one and single purpose of making others' lives miserable. It was a blessing that he wasn't more powerful a wizard.

"And you! Sirius Black! I remember I told you not to glare at me like that!"

"And I still do," Sirius grinned back. "Well done, er..." He applied the same magic on a note sheet to learn the blond child's name. "Well done, Draco Malfoy. Ten points to Slytherin."

"You can't give points to these noisy pests for running rampage !" Filch protested.

"Sadly, now I can," Sirius said. Once, this squib had scared him. Now, as an adult, he found the man had no power over him anymore. "All right, class, let's go back to the room."

As he gathered them back together, Sirius wondered if he counted as a traitor, giving ten points to the enemy house. The wand in his pocket, however, the cold and calm presence with him, assured him it was fine. One day into the summer holidays and nobody would care about points anymore, but the lesson would last, or so he hoped. He was here to teach bravery and justice. Had he lost faith in these? Too bad if he had. The icy touch of his wand reassured him this was the wise choice. He didn't have to be competitive anymore. He was a Gryffindor still, but not a child. And he had already heard enough stories of a certain teacher favouring his own house and earning the hatred of everybody else.

His competitiveness returning to him beyond his control, Sirius decided he would not become something like Severus Snape.

Still, he hoped he would be able to give more points to his own house in the next few days.