Cassie awoke early Saturday morning and quietly prepared for the day while her friends slept. She snuck through the common room and made for the library with her book bag and a scrap of parchment Remus had given her the night before with a list of all the Animagi books she would need.

Dawn stained the castle windows pink as she opened the heavy oak doors and entered the enormous room, filled with seemingly unending shelves that stretched all the way to the ceiling. All the tables and workspaces were empty, which she thanked Godric for; though she had an excuse prepared for anyone who might see her taking out several books on Animagi, running into no one was the better option.

Madam Pince (a severe witch with a hooked nose quite like that of a bird and an unflattering mole on her chin) looked up when Cassie walked in and glared at her with beady eyes, as if to say make more noise than a mouse and you'll be thrown out by the scruff of your neck. Cassie ignored the ill-tempered librarian and headed for the bookshelves, reaching into her pocket and taking out the list of titles.

Advanced Transfiguration Theories by Emeric Switch

From Two Legs to Four: How to Become an Animagus – the Right Way! by Danika Hornbeam

Everyone Has a Beast Inside by Willard Prott

Claws and Fangs: A Memoir of an Animagus by Mica Grouse

Some of the books seemed a little far-fetched, in her opinion, but if Remus and the others had found them helpful, then she might, too. Fortunately, none of the volumes were contained in the Restricted Section, so that made part of her search easier. But as the books did not appear to be very popular or oft used, she began a long and dusty hunt for them.

Her stomach rumbled with hunger by the time she emerged from the sprawl of bookcases, lugging the four volumes to Madam Pince's desk for checkout. The librarian hadn't moved from her perch since Cassie had come in, but she eyed her suspiciously when she slapped the stack of books on the desk.

"Name?" she asked.

"Cassie Alderfair," she replied, wiping her dusty fingers on her jeans.

Madam Pince pursed her lips when she scratched her name down in her book. "And what do you need these books for?"

"Er...research."

The librarian's face soured. "What kind of research?"

"Um, well, I haven't been doing so well in Transfiguration – and I, uh, wanted to do an extra credit project for Professor McGonagall, you see..."

She trailed off when Madam Pince looked her over skeptically. Her heart pounded. Why did she have to be such a terrible liar?

Please, she thought as the librarian looked between her and the books. Please, please, please...

"Very well." Madam Pince pushed the stack of volumes back toward Cassie. "But I expect them to be in perfect condition upon their return: no stains, no tears, no folded corners. Any of the above, and you'll pay for damaging school property."

Cassie nodded quickly, stuffing the books into her bag until it nearly burst at the seams. She turned, about to flee the library, but stopped in her tracks when a sudden thought occurred to her.

"Norvina," she blurted out. Madam Pince's pencil-thin eyebrows rose in question. "Um, Norvina. It's a name. I was wondering if you had anything on it in here?"

Madam Pince seemed irritated that Cassie was still there, but she flicked open a tome on her desk that was the size of Cassie's torso. She swished her wand and the tome's pages fluttered in response. Cassie waited, apprehensive, until Madam Pince shook her head.

"No, can't say I do." She looked at Cassie over her gold-rimmed spectacles. "Another research project for Transfiguration?"

Cassie shook her head, squashing her disappointment. "No. Just, uh, curious."

Before Madam Pince could say another word, Cassie had already rushed out of the library.

xx

"You should take a break."

Cassie glanced up from Everyone Has a Beast Inside when Sirius plopped down beside her on the loveseat in the Gryffindor common room, still dressed in his Quidditch gear. He set his broomstick gently on the floor before giving her a dry look. "You were reading that thing when I left, and that was two hours ago."

"So?" She watched him rake his hair out of his face as he settled back with a sigh. "How were tryouts?"

He shrugged. "Boring. But we found a new Keeper now Weatherly's gone."

"Anyone good?"

"Some fifth-year girl. She's not terrible, but she definitely needs to practice a bit more."

Cassie hummed. "And how's the new captain? They gave it to Fritz Wood this year, didn't they?"

"Yeah, much to Prongs's annoyance. I thought for sure he would get it this year."

"Ah, well. Maybe next year."

Sirius nodded. "Yeah. But Wood's not bad; he's a decent bloke, and he's been working on plays all summer like mad." He shook his head. "Bloke's obsessed with Quidditch – more than Prongs, and that's saying something."

She snorted. "Too true. Speaking of, where're he and the others?"

"Kitchens. I came up to get you and see if you wanted to join."

She shook her head. "No, you go ahead. I want to keep reading."

Sirius stared at her. "Damn, you're in deep. I can't even entice you with food."

"You said it yourself." She rolled her eyes. "Animagi is a long process. If I want to get it down by the end of the year, then I have to start now."

He flicked the cover of her book. "You still need a break. You'll damage your eyes."

"Thank you, Healer Black. I'll keep that in mind. OI!"

He'd tugged the book out of her hands and now dangled it over the edge of the loveseat. "Take a break, Cass."

She crossed her arms. "I'm not even hungry."

"I can think of something else that'll distract you." He tugged at the laces of his robes suggestively.

"You haven't showered yet. No way am I snogging you."

"Then wait while I do." He raised a brow at her.

"Fine." She held out her hand. "But I'll keep reading in the meantime."

He flipped the book in his hand. "Nah." He grinned. "Wait in my bed."

She balked. "Are you out of your mind? The others could walk in at any moment!"

"I'm not saying you should be naked or anything." His grin widened. "Though I wouldn't object if you were..."

She grabbed the throw pillow next to her and threw it at him. He dodged it, laughing, as she grumbled, "Godric, you're insufferable."

"C'mon." He stood up, still holding her book. "Just read it in the dorm."

She relented and followed him up the boys' staircases since he still held her book hostage. He opened the door to the dormitory he shared with the other Marauders and handed her the book.

"I'll be quick," he said, pecking her cheek before retreating into the washroom.

Cassie sighed and collapsed on his bed, the sheets thankfully fresh and made up. He'd already set up his customary posters of Muggle rock bands and motorcycles, though she was grateful he'd foregone the pin-up models. She settled in to read more about Animagi, too engrossed now to stop, as the shower switched on in the next room. She'd only gotten through a few pages before the shower stopped and the door opened, filling the room with steam. She closed the book to protect the pages from the sudden humidity and choked when Sirius strolled into the dorm, wearing nothing but a towel that hung dangerously low on his hips.

"Really?" she demanded when her face went up in flames. "You couldn't have put clothes on first?"

He whistled as he crossed to the foot of his bed and opened his trunk, ignoring her as he rifled through its contents.

Cassie swallowed and forced herself to breathe. It was just Sirius. She'd seen him shirtless before plenty of times. Bloody Merlin, she was being weird.

Relax. Focus on something else.

The scar on his chest finally seemed to be healing. The angry red wound was now pink with scar tissue, fading white, and was hardly wider than her pinky. That was a good thing, she thought, as her eyes traveled from the scar down the hard planes of his stomach before coming to rest on the lines of his hips. Yes. A very good thing...

He straightened, pulling out a wad of clothes and flipping the wet strands of his hair back. His shoulders glistened with water droplets where his hair rested, and he smirked when he caught her red face. "Like what you see, Princess?"

She resisted the urge to hurl her book at the smug expression on his face. "It's all right, Black. But I've seen better."

"Oh?" He cocked an arrogant brow. "I doubt that."

She shrugged. "Maddox Mars did a cover of Witch Weekly one time when my mum was editor. She invited me to the office that day and let me sit in on it. He was bloody gorgeous – Mar wouldn't speak to me for a week after she found out I met him and didn't even get his autograph—"

"All right, all right, I got it," he said, tossing his clothes on the bed. "I'm not a bloody model like your precious Maddox Mars."

She laughed. "Jealous much?"

"Nah." Before she could react, he'd vaulted onto the bed and perched above her, his hands on either side of her head. Water dripped from the ends of his hair and landed on her face, but she found she didn't care that much when she met his eyes. He nipped at her lower lip and she gasped. "I'm not jealous. Maddox Mars can hump a hippogriff, for all I care. I'm the one with the beautiful girlfriend."

She blushed. "Settle down there, Prince Charming."

"It's true." He pressed a gentle kiss to her cheekbone. "I haven't told you that yet, have I?"

"Told me what?"

"That you're beautiful." He drew away when she stilled and met her eyes. "Because you are."

She mustered a nervous giggle. "Uh, thanks?"

"I'm serious." He grinned at his signature pun as he ran his fingers along a strand of her hair. "I dunno how I never noticed it before we were friends. But you have these eyes – all dark and intense and mysterious" —he traced a finger along her browbone— "and an insanely addictive smile" —he brushed his lips over hers— "and your bum is huge—"

She smacked his bicep and he barked out a laugh.

"And to think you were doing so well," she said, though she was smiling, too – blushing like a fool, but smiling.

"Just stating truth." He leaned down and kissed her.

She gave in to him, forgetting her book entirely as she wrapped her arms around his neck and deepened the kiss. She bit down on his lip lightly and he shifted above her, pressing closer, but she froze when she felt what was on her thigh.

"I can stop," he murmured, his voice husky against her neck as he pressed a soft kiss to her skin.

He began to pull away, but she gripped his shoulders. "No. Don't."

He met her gaze, a spark of excitement in his eyes. "Are you sure?"

She nodded, resolute. "I'm sure."

She reached down and grasped him.

He inhaled sharply, but he kept his eyes locked on her as she began moving her hand slowly, rhythmically – up and down, twisting and tugging gently every so often, determining what he responded to and what he didn't.

Heat flooded her as he buried his face in her shoulder and moaned softly. She was nervous, but excited – she'd never done something like this before, something so intimate with another person. She'd tried on herself several times after Marlene had educated them on the finer points, but performing the act on Sirius was almost more exhilarating, knowing that she was the cause for his ragged breath against her neck and his fingers fisted in her hair.

She adjusted her grip when her wrist protested, and he bucked against her involuntarily, the muscles in his arms quivering on either side of her head. Encouraged, she moved faster, her core turning molten at the feel and size of him. He groaned, bringing his mouth to hers again.

Her other hand cupped the back of his neck as his tongue swept in, and he groaned again when she sucked on it, continuing her other ministrations at the same time. He shuddered against her and pulled his head away.

"Are you about to—?" She didn't finish the question, for he was already nodding.

"Yeah," he ground out. "You don't have to—"

She cut him off. "I want to."

All he could do was nod, for in the next moment he'd buried his head in her shoulder again as release coursed through him. She only stopped moving once he'd finished, and they lay for a second, both breathing quite heavily – he from his climax, and she from the sheer exhilaration of it.

He sat up and whipped the towel off, wrapping it around her hand where it still held him. He was still hard while he cleaned himself and her hand, and she stared, marveling, until he was done.

"That was..." he trailed off, slicking back his hair with a grin.

She let out a breathy laugh. "Yeah."

He gestured to her. "Do you want me to...?"

"No, I'm good." She picked up her book again and gave him a cheeky smile. "I have work to do."

"You're so weird."

"So I've been told."

He kissed her once more before he climbed off the bed and walked to the washroom, the towel in his hand.

She whistled after him. "Nice bum, Black!"

He only flipped her off before slamming the door, leaving her alone to laugh and get back to reading.

xx

When Cassie arrived at Potions Monday morning, she found a scroll tied with a black silk ribbon sitting atop her desk. She looked around the dungeon classroom and saw only a few other seats with the mysterious scroll, and it was with a sense of deep foreboding that she opened the scroll and confirmed her suspicions – a dreaded party invitation from Professor Slughorn.

"Let me guess," Alice said as she slid into the seat next to Cassie. "Your wondrous presence is expected for the Slug Club?"

Cassie grunted and tossed the invitation to Alice so she could see. "A Halloween masquerade." She scoffed. "We're only halfway through September. Doesn't this seem a little premature?"

"Well, it says here: Please take your costume choices into extreme consideration and use your time accordingly to plan." She made a noise of disgust. "What a barmy man. But he must have something big in mind if he's sending out the invitations this early."

Cassie shoved the scroll into her bag unceremoniously. "I don't care what's on his mind. I'm not going."

"Can't blame you." Alice shrugged. "There's bound to be all kinds of people there wanting a glimpse of the Great Cassie Alderfair."

"Shh!" she hissed as Professor Slughorn waddled into the room. "Keep it down, would you? I don't want him to think I'm enjoying the attention."

"Good morning!" Professor Slughorn greeted, cutting off Alice's reply. He looked around the classroom and put his pudgy hands into the pockets of his straining waistcoat. "I trust all of you had a productive weekend, and that a select few of you received your surprises this morning?" He winked at several of the students in his "Slug Club" and bestowed an indulgent smile upon Cassie. She shrank lower in her seat. "Today we'll begin work on the Draught of Living Death. Here are the instructions" —he flicked his wand and the blackboard filled with cursive handwriting— "and all your ingredients can be found in the storeroom. If you have any questions or need further instructions, the potion can be found on page fifty-two of your books. Off you trot!"

"I'll get the ingredients," Cassie said, hastily standing as Professor Slughorn waddled in her direction. She fled to the storeroom, not keen on listening to Professor Slughorn's booming flattery so early in the morning – if ever.

The storeroom was filled with students when she pushed her way inside. Since N.E.W.T. Potions was incredibly difficult to get into, only a handful of students from each house were selected and all placed into a single class together. Marlene and Peter hadn't scored high enough on their O.W.L.s to move up with the rest, which just left Lily, Alice, herself, James, Sirius, and Remus. She found the latter and her boyfriend inside, chuckling over something as they collected their own ingredients.

"What's so funny?" she asked as she joined them.

Remus smirked. "We were discussing costume ideas for Slughorn's Halloween party."

"You were invited?" While Sirius had been a coveted prize for Slughorn all these years, she couldn't recall Remus ever receiving an invite, despite his high marks and achievements.

Remus's smile grew as Sirius chuckled. "I was. Sirius wasn't."

"Guess ol' Sluggy doesn't want a disowned Black tainting his little club," Sirius said, flipping his hair arrogantly and smirking.

"Well, that's too bad for him when I show up with you as my date anyway," she said with a grin.

Remus laughed. "Oh, I think I might go now just to see the look on his face."

"He'll die choking on a glazed pineapple, I'm calling it now," Sirius said.

"Wait," Cassie said, "if it's supposed to be a masquerade, how will he know who's who?"

"I'll just Spellotape a sign to my forehead that says I AM THE BLOOD TRAITOR SIRIUS BLACK!"

They all laughed. Remus punched Sirius's shoulder. "C'mon; Lily and James are waiting for us. Let's get these to them."

Sirius sniffed the air. "I don't smell any explosive residue. They must still be alive. Let's go."

Cassie waved as they left the storeroom and went about finding her own ingredients. Most of the students had cleared out during their conversation, leaving her alone as she searched. She had just grabbed a jar of powdered asphodel root when the storeroom door clicked shut, blocking out the classroom beyond and leaving her in the dim cupboard light.

"Not the time," she said to the body that had slipped in behind her, not turning around. She figured it was Sirius, trying to sneak a kiss as he was fond of doing, but she fumbled all her ingredients when Severus Snape stepped into her line of vision, looking like an overgrown bat with his too-large robes and black eyes.

"We need to talk," he said. His eyes were darting everywhere, only settling on her for a second before flicking away again. His face twitched – whether from nerves or disgust that he was speaking to her, she couldn't tell.

It took her a moment to find her voice again. "I have nothing to say to you, Snape."

"It's about Lily." His gaze found hers again and stayed there – beseeching. "I need you to give her a message from me."

"I'm not a bloody owl," she snapped. "And if you couldn't tell, she wants nothing to do with you anymore. Leave her alone."

Snape's face rippled with pain. "I just need her to know that I'm sorry. I never meant to—"

"Never meant to what? Insult her? Degrade her in front of the whole school?" Snape seemed to deflate at her words. "And what on Earth makes you think I'd do your bidding after what you did to James last term? You're lucky Lily cared enough not to have you expelled or carted off to Azkaban for using such a spell on him."

"I just need to explain—"

"No," she said coldly. "I don't want your excuses, and Lily doesn't, either. Just drop it, Snape. You have your little snakes as friends now. Do they even know you're talking to me? Do they know that you're trying to mend your friendship with a Muggle-born? I wonder how they'd feel about that if they found out?"

Snape looked so desperate she was surprised he hadn't fallen to his knees yet. "You don't understand. Lily, she – she's everything to me. I would never hurt her—"

"But you did." Snape flinched back as if she'd struck him. "And no amount of apologies can ever change that. The only way you can maybe even be forgiven is changed behavior – but we both know you're too much of a coward to stand up to your friends."

"Please." He stared at the floor, his hands clenching and unclenching. "You know nothing, Alderfair. Please, just tell her I want to talk to her—"

"No." Cassie shoved past him, making for the door. "You made your choice; she made hers. Now move on."

"How dare you?" he hissed, whirling on her. Cassie stopped and turned to face him. He glared at her, his sallow face turning red.

She shifted the ingredients in her arms, freeing her hand to plunge into her robes if she needed to draw her wand. "How dare I what?"

"How dare you be such a hypocrite!" Cassie blinked at him, startled. "Claiming that I'm a coward for not standing up to my friends, when so are you!"

"Excuse me?"

He curled his lip at her. "I know what you did with Avery and Regulus. You led them on – fooled them into thinking you were willing to work with them, but instead you used them to get answers only for yourself. And when they gave you all they could, you dropped them like they were nothing. You crawled right back to your cubs without a care in the world. Do you know the danger you put them in? They betrayed Carlisle for you and your lunatic of a brother. Reg was smart – he had an alibi. But Avery? Carlisle got to him. She went to the Dark Lord himself. And now Ed gets his whole family taken hostage because of what you did to him. By listening to your friends when they told you he couldn't be trusted, even when you know he could."

Cassie's blood had frozen in her veins. "What?"

Snape scoffed. "The Dark Lord doesn't accept failure from anyone – or betrayal. The Averys have a kill order on their heads. If Ed screws up again, or tries to undermine the Dark Lord in any way, then his family gets executed. Him, his mother, his father, his sister. Did you even know he has a sister? Evangeline. She's only seven."

It took all her will to keep a hold on the ingredients. "How do you know this?"

Snape only gave her a look of disgust. "The lions aren't the only ones who watch each other's backs."

He swept past her, purposefully knocking his shoulder against hers. A vial tumbled out of her arms and shattered on the floor. She barely heard it.

"Snape." She turned. He glanced over his shoulder, the loathing clear on his face. She struggled for words. "I'm so sorry."

He glared at her and said, "Tell it to someone who cares," then left.

Cassie stared at the broken glass at her feet and the red liquid that looked like blood.

What had she done?