Remus' first class the next day was Arithmancy, and he was inordinately nervous.

James was in his class, fortunately, and Remus was happy for the fact; otherwise, he wasn't sure whether he'd survive, especially not whilst holding a clear sandwich container with a Bowtruckle inside. He couldn't imagine the questions that he'd get, and that was on top of the awful way that Professor Craff was sure to treat him. Remus had stumbled across Craff in his first year once, while on his way to a detention with Professor Questus (it was a long story), and she hadn't exactly been friendly.

"I'm really, really nervous," he confessed to James as the two of them walked down the corridor to Arithmancy. "I feel a bit ill, actually."

"Need to go to the Hospital Wing?"

"No. I just… Professor Craff doesn't like me."

"That's ridiculous. She's never met you."

Remus lowered his voice to a near whisper, even though no one was around. "James, she hates me. She doesn't like werewolves."

James ran into a wall. Remus laughed, but James wasn't smiling: he simply took a step back, checked to make sure his glasses weren't broken, and rubbed his reddening nose. He looked furious. "She doesn't like you just because you're a werewolf?" he hissed.

"Shhh, James, you're too loud…."

"Shut up, Moony! This is a travesty! That can't be allowed! Why does she even still teach here? That's flat-out bigotry! Can't we tell Dumbledore to sack her? Has she ever hurt you? Said anything rude to you? I'm gonna kill her!"

"James! Stop it! It's normal."

"WHAT?!" James' eyes nearly bugged out of his head. "No! That's not right! It's awful! It shouldn't be normal at all!"

"But it is. I mean, it's unpleasant, but I can't blame her for being afraid of furry, fanged, four-legged monsters…."

"But you're none of that right now!" said James, waving his hands in the air so violently that Remus was afraid that he'd hit him. "Why are people so stupid?!"

Remus stopped here, turning to glare at James. He crossed his arms over his chest. "James, I warned you, didn't I?" he said. "I warned you that not everybody was going to like me. I warned you that prejudice was unavoidable. I warned you of all that when you said that you wanted to stay my friend last year. That was almost a whole year ago, and we've escaped most of that so far... but it's unavoidable, really."

"You're not a monster, Moony!"

Remus licked his lips, exceedingly nervous to be talking about this subject in the open… but he continued anyway. He had to make James understand. "Perhaps not. But you've never been to the Ministry with me. You've never been to St. Mungo's with me. You only ever see me as I am with you, my parents, and the professors. But that's not how everyone sees me, and I need you to understand that I am used to it. I know how to deal with it, and I need you to follow my lead instead of getting angry about it all the time."

"But..."

"You pity me entirely too much."

"But I..."

"All I ask is that you let me complain sometimes without trying to fix my problems... Prongs." Oh, the nickname was so stupid. But it was nice all the same—it felt endearing in a way that the name "James" did not. "Just try to get a seat next to me... and don't yell at Craff, no matter how questionably she treats me. Keep that Beater temper in check, please."

James rolled his eyes and smiled. "I'm a not a Beater yet," he said, but Remus could tell that the ice was beginning to break.

"You will be, won't you? Unless the Quidditch Master James Potter is beginning to doubt himself?"

"Never, Moony."

"Have it your way, Prongs."

They arrived at Craff's classroom, and the knot was mostly gone from Remus' stomach by now. Fortunately, there were two seats next to each other in the back, so James and Remus took them immediately before anyone else could. Remus felt incredibly awkward, carrying two books with a Bowtruckle in a sandwich container resting on top. He unpacked his things and set up his inkwell without looking at Craff (who was standing at the front of the classroom, Remus knew, but he was too afraid to behold her expression).

"She won't stop staring at you," grouched James. "Glaring, more like. Awful woman."

"Don't look at her, then," advised Remus.

"All I ask is that you let me complain sometimes without trying to fix my problems, Moony," said James, quoting Remus' words from earlier, and Remus snorted. He hit James, who hit him back—and all of a sudden, Remus was in a much better mood. He looked up at Professor Craff, still snickering slightly, but the joy drained out of him as soon as he noticed that she was staring back at him, eyebrows furrowed in a perfect expression of anger. She was a rather pretty woman, but her face was bony and sharp, and her straight brown hair was pulled back into a low plait. Her eyes were dark, both physically and emotionally, and Remus had to look away.

"Can I whack her with something?" asked James.

"Absolutely not."

Remus had advised that James not look at the woman, and now he decided to take his own advice. He took out a piece of parchment, ready to take notes, and looked everywhere and anywhere but Professor Craff. He was relieved when Craff finally began the lesson, even though he might've liked to goof around with James a bit more if it had been anyone else teaching the class.

"Arithmancy," announced Craff, her heels clicking as she walked to the blackboard, "is the study of numbers and how they relate to magic. That sounds easy, but it is actually very complicated." She tapped the blackboard with her wand, and a simple equation appeared. "Has anyone studied Muggle maths, by chance?"

Remus had. His mother was a Muggle, so of course he had studied Muggle maths—his mother wouldn't have had it any other way. He looked around the room: Evans was raising her hand, and so were three others. Remus tentatively lifted his hand in the air at shoulder height.

"Good," said Craff. "Four. That's more than usual."

Remus lowered his hand. She hadn't included him.

"It's five, actually," said James loudly. "Evans, Remus, and then three other irrelevant children. That's five. For an Arithmancy professor, you can't be very good at maths."

Craff's face went red. "A little more respect, please, Potter. This is an environment of learning, and we do not mock mistakes in my class."

"Unless they're stupid ones, right?" said James, and he winked as the class burst into surprised laughter.

"Detention!" said Craff.

"Worth it," said James.

Remus rolled his eyes. "She's only trying to ignore me, James. It's better than being openly hostile, at least. Leave her be."

"Nah."

"James!"

"Please, class!" cried Craff. She nearly had to shout, for the din in the room was reaching horrible levels. "Back to the lesson! Anyway, I suspect that the rest of you either learned wizarding maths from a parent or tutor. Those of you who did not learn maths at all: I hope you read the textbook, because you're going to need to play a bit of catch-up from here on out. Those of you who did learn Muggle maths: it is different from wizarding maths, yet simultaneously similar. Can anyone tell me what this equation represents? 20x + 71 = 131. Potter, please remove your feet from your desk."

James did not remove his feet from the top of his desk. He was leaning back in his chair haphazardly and smiling winningly at Craff.

"It's just an equation," said Evans, and Remus was thankful for the change in topic. It looked as if James was not going to be obeying Craff anytime soon.

"Yes, it is. Explain it in words."

"Erm… If there's three each of something, then x represents the number of that something. When you add eight, then the answer is sixty-eight."

"So x is…."

"Three," said Remus.

"Anyone?" said Craff. "It's a very easy equation."

"Three," said Remus.

"Someone? Anyone."

"Three," said Remus.

"Remus says it's three," said James.

Craff looked a bit constipated. "Very well done, James."

"Well, I didn't do a thing. I just said what Remus said, except louder, because clearly you're hard of hearing. You should be congratulating Remus, not me. Well done, Remus!" said James. He clapped his hands enthusiastically, and a few other members of the class joined in.

"When we get out of this classroom," whispered Remus, "I am going to murder you slowly and painfully."

"Worth it," said James again with a cheeky grin.

"Can anyone come up with a scenario in which this equation would prove true?" said Craff, and her voice seemed to be getting louder and more desperate by the second.

"Yeah," said James. "So there are one-hundred-thirty-one questions on a test, and our Arithmancy professor lets us complete the test together, as a class. There are twenty-one students in this class. One of them, Remus, answers seventy-one of them correct before anyone else can, because he's an absolute genius, stand-up bloke, kind person, and altogether worthy of your attention. The other twenty students answer x questions correct. That x is equal to three, which is about 4% of the work that Remus did.

"Therefore, we can conclude that the combined efforts of Remus Lupin and every single other student in this class is the equivalent of a one-hundred-thirty-one question test. Alternatively, you could give the entire test to Remus. Does anybody know how the equation would change in that case?" James surveyed the class. No one answered, and James clicked his tongue disapprovingly. "Why, it would be 131=131, of course! Is my arithmetic correct, Kirsten?"

"Your arithmetic… is correct," she said reluctantly, and James tried to high-five Remus. Remus was not amused and didn't high-five James back, so James just ended up smacking him in the face. The class tittered, and Craff pressed her lips together very tightly. "I was looking for a rather… different approach, though, so I'm going to give you my own equation. Let's say you buy three broomstick-cleaning kits, x, for twenty Galleons each. You buy a broomstick for seventy-one. The combined cost is one-hundred-thirty-one Galleons."

"Rubbish," said James. "You can't buy a good broomstick for seventy-one Galleons. A good broom's worth at least seventy-six."

"Anyway," said Craff loudly, "the number one-hundred-thirty-one would change if you bought more than three kits, would it not? Anyone know what the total cost would be if you were to buy nine kits?"

"Two-hundred-fifty-six," said James. "If your broomstick arithmetic was correct, that is, which it's not. You simply cannot buy a good broomstick for less than seventy-six Galleons. And, besides, the equation is rubbish anyway. If one-thirty-one weren't a constant, then you should have labeled it y. Would've been less confusing for us."

"Two-hundred-fifty-one," said Snape, who was sitting next to Evans.

Craff rather looked like she'd just eaten a lemon. "Correct, Mr. Snape. Thank you. My point is, mathematical formulas are used to predict the outcome of a situation. They get a lot more complicated than this, of course, but you get the general idea. Now, magic—like real-world events—can be predicted using numbers. Arithmancy attempts to make sense of these numbers in order to predict how magic works. It is important to know, however, that while magic can indeed be predicted… there are a lot more exceptions to the rules of magical mathematics than there are to Muggle mathematics. In some cases, magic doesn't make sense at all. But arithmancy focuses on the magic that does make sense, and it can predict its outcome with frightening accuracy."

Remus had a question, but he didn't want to ask it. So he wrote it on a piece of parchment and slid it over to James very inconspicuously. "Could you ask this for me?" he asked in a very, very quiet voice. "I don't want to stand out any more than I already have."

James shot his hand up into the air. "Remus has a question," he said, and Remus buried his face in his hands and groaned.

"What's his question?" said Craff.

"Aren't you going to ask him?"

Craff didn't say anything, but she turned her head ever so slightly towards Remus. "Er," said Remus. "What's the… what's the difference between science and magic, if magic can be predicted? I always thought that magic was magic simply because it was unpredictable. After all, Muggles say all the time that magic is only science that they haven't figured out yet."

"Yes, good question, Remus!" said James. "Isn't it a good question, Kirsten?"

Craff, again, did not acknowledge James' comment. Remus was thankful for that, actually. "Arithmancy is not science," she said simply. "The rules of arithmancy and the rules of science do not coincide. We will be conducting a lot of experiments, but magic is the extra factor that we must consider when we do so. Instead of equations, we use charts." Craff pulled down what looked like a map from the ceiling, but it was actually a list of numbers. Some of them seemed to be strange squiggles that Remus didn't even recognize.

"Unlike science, there is no logical correlation between these numbers. There are no precise equations. We do mathematics in arithmancy by consulting these charts."

"Where'd you get the numbers, then?" said a boy from Slytherin.

"Experimentation. Magic can only be predicted through trial and error, because the magical element is entirely unpredictable. Arithmancy is all about taking past results, portraying them in terms of numbers, and then applying them to the future. It's a combination of Muggles sciences and mathematics, but it's not really either. I personally believe that all magic can be predicted through numbers, but there are many types of magic for which we've not yet figured out how to do so. The question is, though: Why? Can anybody tell me why arithmancy might be useful?"

"Potions," said Snape.

"Precisely. Determining the amounts of ingredients and number of stirs is arithmancy's most common use. Any others?"

"Determining the effects of an unknown spell?" proposed Evans.

"Yes, good."

"Determining how different factors contribute to the effectiveness of a spell," said a Slytherin girl, "like location and time cast."

"Very well done."

"Determining laws and limits of spells," said James.

"Exactly."

"Wand-making, like Ollivander does," said a Gryffindor boy.

"Indeed."

"Curing magical maladies and curses," said Remus.

"Spell creation," said Snape.

"Very good, Snape," said Craff. "And those are the basics, though there are other minor uses for the craft. Now, if everyone would open to page two, there are a few examples of how to use a number chart..."

Both Remus and James were somewhat furious when they left Arithmancy that morning. "She's awful!" said James. "That terrible, horrible hag!"

"She was acting perfectly reasonable," said Remus. He was clutching Francine's container with such force that he had to balance it atop of his books instead, lest he crush it. "It's you who was being idiotic. I don't want attention called to me, James! I warned you that she didn't like me! I told you to follow my lead! I told you not to try to fix my problems! I could have dealt with it so much better than you did!"

"By doing what, Moony? By staring at your desk and acting resigned to it? Like you deserve it? You don't! This is nonsense!"

"It may be nonsense, but it's also my life! That was nothing, James! Nothing! She pretended like I didn't exist, yeah, but at least she didn't tell me to off myself!" Remus wasn't speaking very loudly, but he felt as if he was. He pulled James upstairs and into the dormitory; he'd be a bit late for Care of Magical Creatures, but he needed to speak to James without fear of others overhearing.

"Tell you to… what?" said James. His face was bright red with anger. "They tell you to what?"

Remus held up a thumb. "One: the lady on the Knight Bus after I got bitten. My family and I were on the way to St. Mungo's. She told my mother that it would be better if I died. Mum was just as angry as you are now, but she had much more reason to be so." He held up another finger. "Two: the Healers at St. Mungo's. Asked if I wanted to be put down. They do that every time I go, did you know? It's just common courtesy. Manners. Because what werewolf would ever want to live?" A third finger. "Three: Professor Questus. Mentioned that he had no proof that werewolves were people, therefore he couldn't publicly choose a side. Implied that he'd support mass werewolf execution if it were a bit more plausible."

He held up a fourth finger before James could insult Professor Questus. Remus didn't want to hear that right now. "Four: teenagers from Durmstrang outside one of the places that I used to live. Told me that I'd jump off a cliff if I had any decency. Used the Cruciatus Curse, though they weren't very good at it. Five: the Ministry. Every time I go. Ragfarn in particular likes to imply that he doesn't want me alive and would gladly kill me himself if it wouldn't get him sacked. Six: Sirius' father—I should think that's self-explanatory. Wrote a whole article last year about how he wanted me dead. Seven: Werewolf Capture Unit. They obviously want to find me and get rid of me.

"Eight: a private Healer that Dad hired when I was nine. She found out what I was the very first time she came to heal me, of course, and there was an argument that ended in a violent duel. Dad broke his nose. It was kind of funny, actually—he spoke like a duck until he managed to get it fixed. Nine: Sirius! Remember what he said about werewolves in our first year?"

"He didn't mean that… he didn't know what—who you were…."

"Not who I am, James: what I am. It's not offensive. I refuse to believe that a werewolf is part of who I am. Anyway. Ten: my own father, before he came to his senses. He didn't even want to heal me when I was bitten for a couple of minutes… er, don't tell him I told you that. He's quite embarrassed. Anyway." Remus was holding up ten fingers now, and he brandished his flat palms in James' face. "I'd go on, but I'M OUT OF FINGERS, as you can plainly see. It's a pity. I could probably count on your hands, as well, if you want."

"Remus, I—"

Remus realized with a jolt that he had overshared. He was used to being able to talk about these things without restraints with Professor Questus, but he often forgot that the same did not apply to James. "Gimme a second," he muttered; he leaned against the wall and breathed deeply. In through his nose, out through his mouth… it was a while before he was feeling normally again, though he didn't know how long.

He opened his eyes. "I'm sorry," he said, his face now feeling extremely hot. "I shouldn't have said all that. It's not so bad as I made it sound. But… truthfully, James, everyone wants me dead. It's more or less a fact of life when one is a werewolf. And I've experienced far worse things than people who pretend I don't exist… I've been very lucky at Hogwarts, but that doesn't mean that it doesn't happen. And Craff is doing fine, honestly. She doesn't think that she can treat me like a student, so she doesn't treat me… like anything at all. Which is preferable, obviously. Does that all make sense?"

James nodded. Then he stamped on Remus' foot with the heel of his boot.

"Ouch!" said Remus, rubbing his foot. "Seriously, James? What was that for?" James was wearing his Care of Magical Creatures boots, since they had that class later that afternoon, and they were heavy and thick. Remus' toes smarted considerably. "What did I do to deserve that?"

"Oh," said James, arranging his face into one of mock confusion. "But I thought turning into a werewolf hurt."

"It does!"

"I thought you end up with injuries a lot worse than that after full moons."

"I do!"

"So if you've experienced something worse, then—according to your own logic—I reckon I should be allowed to stomp on your feet a bit. You allow Craff to treat you badly because you've experienced worse things, so why not me?"

Remus sighed. "That's not the same thing, James. And I am all right with you stomping on my feet, I guess... just not for no reason. You're gonna need a really good reason to stomp on my feet for me to be all right with it."

"Exactly! There isn't a reason for Craff's behavior, mate. It isn't warranted one bit."

"Agree to disagree," said Remus. "You know, Professor Questus once made an extensive argument regarding that. You know, that prejudice isn't warranted and such. But I still want to think the best of people... after all, it's not like getting angry with them will change anything." Remus sighed once more and rubbed the bridge of his nose. "I guess my real problem is that you called a lot of attention to me in class today, Prongs. Makes it harder to keep my secret."

"Agree to disagree," said James. Before Remus could argue, James took his arm and began to pull him towards Care of Magical Creatures class. "Come on, we're already late. And…." James grinned. "You really like those nicknames, don't you?"

"Shut up. And since when is the great Quidditch Master James Potter worried about being late?"

"Since the Great Quidditch Master James Potter is taking all the electives!" James grinned and yanked at Remus' arm a little bit harder. "Good talk, mate. Now let's go to a class that's bound to be a lot more fun than stupid Arithmancy!"

It was nice to meet up with Sirius and Peter in Care of Magical Creatures: as much as Remus liked James, it had been tiring to be alone with him. James and Remus were five minutes late, but Kettleburn didn't seem to be fazed. James had labeled him as "easy-going" and "stupid" on the way to class—Remus agreed with the first, but wasn't sure about the second. "Today, we're going to be studying Bowtruckles," said Kettleburn. "I've asked young Mr. Remus Lupin here to conduct a bit of an experiment with my Francine—she's skittish around people, you understand, and I want her to get used to them. How is she, Lupin?"

Remus held up the container. He was extremely embarrassed to be called out in the middle of class again. "She's okay," he said. Kettleburn waited, as if he expected Remus to say something else, but Remus didn't. What was he supposed to say? "Yeah, Francine's still terrified of me because I'm a werewolf"?

"Good," said Kettleburn awkwardly, clapping his hands. "Bowtruckles are very shy, now, so we have to be careful around them. Can anybody tell me where you can find a Bowtruckle?"

As hands shot up all around him, Remus sat back and stared into Francine's beady little eyes. He wished that he were a Bowtruckle—her life was bound to be a lot simpler than his, even though she was trapped in a small container with a terrifying werewolf.

AN: Today on "letters and days of the week that have similar vibes"... "Friday" and "I"!