Sirius looked on in shock as his little brother proceeded to waltz into the common room, grinning like an idiot.

"Regulus?" he asked incredulously. "What are you doing here?"

Remus, Peter and James stared accusingly at Lily, who shrugged.

"I didn't invite him," she said blankly.

"Liar!" Peter cried, astounded. "You just said you did!"

"He's right, Lily, you know you did." Remus added reasonably.

"But I really didn't!" Lily replied defensively. "I invited - "

"She invited me," Severus Snape said, gliding smoothly into the room behind his fellow Slytherin. "And I brought Regulus along because I am not dimwitted enough to venture into the lion's den alone."

"And..." Regulus added leadingly.

Snape glared at him and continued. "And because if Evans wants to have even the slightest chance of this working, Black needs family present."

Regulus rolled his eyes, and Lily smiled at Snape and said, "Thank you, Severus. That was a really good idea."

Matilda muttered something that sounded suspiciously like 'Sevvie,' and burst into a fit of giggles along with Bertha Jorkins. James glared at them both, and at Lily as he said,

"Why did you invite Snivellus?"

Lily raised an eyebrow at him. "Because I thought he'd be able to help," she answered, her cheeks only a little bit pink.

Sirius stood up and marched over to James and Lily.

"What is going on?" he hissed, glaring over at Snape and Regulus. "What is Snivellus doing here?"

"Didn't I just tell James? Why weren't you listening then?" Lily asked irritably.

"I went deaf with rage when he walked in." Sirius was still glaring darkly at Snape, who had noticed and returned the favor tenfold.

Lily resisted the urge to roll her eyes and call him a drama queen, but only barely. Instead she opted to say, "James, Sirius, pipe down and let them try to help you. Regulus is your brother, Sirius!"

"I've got no problem with him, Lily," Sirius said pointedly, as James nodded emphatically next to him.

"Aw, come on you two!" Matilda had just bounded up next to them and cocked her head to look at the two boys reproachfully. "Just let him stay! Can't you see Lily has a plan?" She smiled knowingly at Lily, who just looked back at her, eyebrow up again.

Sirius thought for a moment, eyeing Matilda calculatingly.

"She better have one hell of a plan, then," he said, and with that he turned around and flopped back down in his seat.

James watched his retreating friend with something akin to betrayal on his face, then looked at Lily and asked, "Have you got a plan, then?"

Lily too in the wary yet hopeful expression on his face, smiled, and said, "Of course I do, James. It'll be fine, I promise. We'll be in Hogsmede before you know it."

James perked up at the reminder that it was he who was going to Hogsmede with Lily later, not some slimy git, and gave in willingly.

Once everyone was resettled and chairs had been found for the Slytherins, Lily clapped her hands and looked at Sirius.

"Sirius," she said, eyes darting to Severus and Regulus, "If you wouldn't mind very much, could you update these two as to why you don't want to quit?"

Sirius frowned and nodded. "Well Reggie," he said, pointedly excluding Snape. "They claim I'm hurting them. I don't see how that could be true. I still hang out with them, and the Billywigs don't make me want to hex them or put bear traps in their beds, so..." he shrugged, as if to convey his own confusion at the abnormality of his friends. "And they also say I'm hurting myself, but if I want to, why can't I? It's my body and if I don't mind being bald or impotent, why should they?"

Regulus stared at him, mouth hanging open slightly. "Billywigs can make you...bald?" he whispered, reaching a tentative hand up to run his fingers through his own glossy hair. "And...does...impotent mean what I think it means?"

"Impotent," Sirius said carelessly. "You know, like when Great Uncle Lyccris was mauled by a Bowtruckle and it got his - "

"Yes, alright, thank you Sirius!" Regulus said in a high pitched voice, wincing slightly. Sirius frowned at him.

"What's your problem?" he asked curiously. "Afraid some of my billywig germs will rub off on you?"

Regulus flushed and stuttered slightly. "O-of course not, Sirius! I'm just really worried about...you."

"Please, Regulus," Snape said idly. He gave Sirius a condescending look and stated, "He's concerned because he, like much of the rest of the Slytherin house, have been stinging for quite some time now, completely indifferent to the consequences."

Sirius blanched. "Slytherins are stinging too?" he asked unhappily. "Where did you lot find out about them, Reggie?"

Regulus shrugged and adopted a superior look. "Oh, you know, here and there."

Lily raised an eyebrow at him, and he flushed slightly and added, "That hippie bloke Bella used to talk to. He told me about them."

Sirius' jaw dropped. "That's who told me!" The two brothers grinned at each other for a few moments, until Sirius realized something and scrunched his face up distastefully.

"You mean I've been doing something like the Slytherins?" He looked faintly disgusted at the notion.

Snape smiled nastily. "I guess you might just be one of us after all, eh Black?"

Sirius' face was now the picture of revulsion. "No! Sorry, Snivellus, but I'll never be one of you slimy Slytherins!"

And with that he turned his back on them, leaving Snape grimly satisfied and Regulus slightly upset.

"Lily," he said contritely. "I want to quit. I don't want to do Billywigs anymore. I'll do whatever I have to. Can you help me?"

Lily smiled at him. "Of course, Sirius." She nodded happily at Snape. "We'll do everything we can."

"I can't believe you're going to go!"

"Matilda, it's just one date."

Matilda threw herself down on Lily's bed. "To you it might be just one date, but to Hogwarts, it's a death sentence, Lily!"

Lily rolled her eyes as she fixed her earrings in the mirror. "Matilda, I promise, if I notice walls crumbling around me, I'll break it off and come back, alright?"

"Lily, please!" Matilda said anxiously. "It's not worth it!"

Lily turned on Matilda, eyes flashing, and said, "Please, Matilda. Stop with all this rubbish and act like an adult. You can't honestly believe that my dating James will actually hurt the school. And think about it; if I don't do this, James may go back to Billywigs, which we don't want. If he does, Sirius will too! And look where we'll be then!"

Matilda blinked and thought about it for a second. "Where we were before? Only aware of it?"

Lily sighed. "I'm going, Matilda, and that's that," she said tersely. "And you're not to follow me, understand? I swear, if I even see you walking by, I will suspect the worst and won't be responsible for my actions."

Matilda's eyes widened. No one in Gryffindor wanted to be on the wrong end of Lily's wand. Especially not after Easter of fourth year, when she'd hexed James to bits after the butterbeer incident.

"Okay, Lily, I'll leave you alone." she said warily. "But honestly, I'm worried about this."

Lily frowned. "It'll be fine, Matilda. I promise."

Matilda nodded reluctantly, yawning a bit. "Alright. Well, all that intervention-ing really wore me out. I'm going to take a nap. Is that alright, Lily?" she finished ironically, raising her eyebrows at her friend.

Lily grinned abashedly as she grabbed her bag and headed out of the room. "Yes, I suppose so."

Matilda shook her head with a grin of her own and laid back on her bed, curling up in a ball and falling asleep.

"Sirius, I need you to tell me again."

Sirius grinned. "Lily Evans and you are going to be in Hogsmede together in about a half an hour." He checked his watch. "If you're ready by then, I mean. You priss," he added nonchalantly.

James was standing in front of the mirror in their bathroom, combing his hair for the fifteenth time. Sirius was standing behind him, messing it up occasionally and earning himself venomous glares.

"Stop that," James said distractedly, giving up on his hair and now fussing with his robes. "I can't believe she agreed!"

"Neither can I," Sirius said gravely. "The girl could do so much better."

James glared at him. "I mostly meant because of the Theory, Sirius."

Sirius grinned unrepentantly. "Oh, yeah, and that too."

"I mean," he continued nervously, "What happens if the walls start crumbling or something?"

"It's alright James," Sirius said. "I've got the letter in my room. I'll post it to that Weasley, and he'll meet up with us, and in no time at all, you and Lily'll be acting all disgusting and sappy, and no one has to die."

He said it so matter-of-factly that, for a moment, James felt that everything would be alright.

Then Sirius continued. "So all you have to do is not make a complete arse of yourself in front of her, and you'll be fine!"

James moaned and snatched up the brush again, pulling it desperately through his hair.

"Thank you, Sirius," he said unhappily. "You always know just what to say."

Twenty minutes later found James flying through the room in a panic. "Sirius! You sodding arse! You hid my glasses, didn't you!"

"James, I -"

"No, Sirius! This is too important for your little games, d'you understand me?" James glared angrily at Sirius as he pulled the bedclothes off of his bed and lifted the mattress. "This is not the time, Sirius! Where did you put them?"

Sirius watched him in amusement. His hair had gone askew, there were patches of bright red on his cheeks, and his glasses kept slipping down his face as he looked for them.

"James, where was the last place you saw them?" he asked, carefully hiding his grin behind his fist.

"Well, I was wearing them. I -" James froze in the act of pulling Sirius' mattress off of his bed and lifted a hand up to feel at his face. "Oh."

"Oh." Sirius repeated, now grinning openly at James. "Oh?"

"Oh..." James said meekly, setting Sirius' pillow back on his stripped bed and stuffing a handful of feathers back inside. "Sorry. Just let me -"

"Just go, James," Sirius said fondly. "I'll fix it."

"Are you sure? I should stay here and help..."

"Lily is waiting."

James perked up. "Sorry Sirius! Bye!" He dashed out of the room, pausing only momentarily to fix his hair before leaving Sirius alone in the middle of what looked more like a war zone than a bedroom.

Sirius considered the mess for a moment before shaking his head and wading through the bedclothes to his trunk, where he extracted a letter addressed to one Bilius Weasley. He met Remus on the stairs on his way to post it.

"You may not want to go in there," he said, jerking his head at their dormitory.

"Why?" Remus asked suspiciously. "What did you two do?"

"Nothing worse than usual," Sirius said, eyeing him. "What's your problem?"

"Nothing," Remus sighed. "Only I've just spent the last hour or so convincing Snape and Regulus to leave."

Sirius snorted. "That's shocking. You'd think Snivellus would want to get out of here as soon as possible. Someone might accidentally hit him with a cleaning charm."

Remus shook his head bemusedly. "He was all for leaving, actually. It was Regulus. He wanted to wait for you to come back down, even though I told him you'd be up there with James until he was ready to leave. He kept saying he'd wait. Then James came down, and Snape said something to him about Lily, and they started fighting. We had to force them apart." Remus grinned slightly. "James was really lucky Lily missed that bit. She came down about a minute after we kicked the Slytherins out."

Sirius grinned. "How did I miss that? Say," he added, pulling Remus with him down the stairs, "Come with me to post this."

"You just don't want me seeing what you and James did to the room." Remus said, allowing himself to be led through the common room and out into the corridor.

"Why would I care?" Sirius asked casually. "It's not like he set fire to your bed."

"This time."