Author's Note: Realized that last chapter was a little shorter than normal, so here's another one! Climax!
As soon as Sirius was taken to the hospital wing, Peter jogged to the library. He found Remus sitting at a large desk with books scattered around him. He had his head resting on Sirius's hand, the curly black hair more disheveled than ever. Peter stood across the table. Remus didn't even look up.
"I can't figure it out, wormtail." Remus sighed. "Was the fountain a magical artifact? Was the water a potion? Was it cursed or charmed? Was it something else in the room all together? I just don't know."
"That doesn't matter now, Remus! Sirius was taken to the hospital ward!"
"W-what? W-w-why?" Remus stuttered out of astonishment.
Peter leaned in close so the other students wouldn't hear.
"Is it your time of the month? Maybe your furry little problem?"
Remus went up to the front desk. "Excuse me, what's the date, sir?" The old man woke from his sleep and pulled a small calendar out of his desk. "February 23rd son."
"What does that mean, Remus? Peter asked.
"Todays the full moon, and I forgot. That's what it means."
"Remus! You never forget!"
Remus stood frozen. The realization had just hit him. He couldn't move. Sirius would hate him after this, he was sure of it. He finally blinked and looked at Peter. "We need to find James. He's probably under the invisibility cloak sitting on his bed."
As fast as they could, (they were getting pretty used to their new bodies), the two ran up the steps to Gryffindor's common room. They burst into the boys dorms.
"James take the bloody cloak off, Sirius is in trouble." Remus demanded.
Nothing moved.
"It's a full moon." Remus shouted.
There was a rustling and suddenly Peter Pettigrew appeared.
"James!" The voices of James and Sirius said in unison.
"Well what are you two waiting for? Let's go, idiots!"
Back in the hospital ward, Madame Pomfrey was just putting Sirius's arm around her shoulder. "Come on love, It's almost time." The two slowly walked out to the Womping Willow tree. Madame Pomfrey tapped on a root, and the ravenous branches froze. They hurried into the tree. Sirius was barely conscious through any of this. All he could focus on was keeping his eyes open. Pomfrey helped him into the Shrieking Shack.
"Good luck, dear." Her sad eyes told him she hated leaving him alone.
Sirius mustered enough strength to mutter, "You've got this all wrong…I'm… not Remus!"
But she didn't hear him. She'd already left.
Sirius dragged himself over to the boarded up window. He'd been in she Shack loads of times, but never alone; and never as a werewolf. He peeked out a small crack in the boards. He could see the sun setting in the distance. He had never been so scared in his life.
Meanwhile, the three non-werewolf marauders were dashing to the Shrieking Shack.
"Peter, get Dumbledore!" Remus shouted.
"We'll get detentions for a year! We'll get kicked out of Hogwarts!" Peter exclaimed.
"Would you rather get kicked out of Hogwarts or abandon your friend?!" Remus screamed, out of breath.
"I-I- I'll go get him!" Peter took a left at the next corner, while James and Remus ran on. Remus tapped the root and let James go in before him. He'd done this many times. Never as a human. He looked to his right. The moon peaked over the Hogwarts lake. Remus stood, amazed by it. He had always hated and despised the moon for obvious reasons. But now he found it beautiful. Perfectly round, centered, shining. He was dazed by it. He thought, What if I just turned back right now? He was awaken from his daze by the screams of his own voice. He was ashamed for thinking about leaving his friend to suffer, even for a second. He followed James into the tunnel.
The screams of Remus's voice were deafening. Becoming a werewolf is the most painful thing any living creature can experience.
When Remus finally entered the Shack, what he saw was horrid. So this is what they see. He thought.
"REMUS HELP ME" Sirius screamed. Tears were streaming down his face. "TELL ME WHAT'S HAPPENING"
Remus knelt next to Sirius. He was thrashing on the floor. "Try not to move! Try not to move! It makes it hurt more. Your bones are breaking and fusing back together! Stop moving!"
Sirius stopped moving. His eyes were wide and he was sweating with fear. He screamed again, louder this time.
"Your heart stopped. Hold your breath. That usually helps me." Remus tried as hard as he could to keep his voice calm.
Sirius slammed his hands into the ground, blood dripping from his fingertips.
"That'll be the claws. You can do this Sirius. Hold tight. Dumbledore will be here soon I promise!"
"KILL ME!" Sirius cried.
James had seen Remus transform hundreds of times. He'd never thought it to be so painful. Remus had to have controlled himself.
Sirius was almost fully transformed. He looked around with bright yellow eyes.
"Remus! You need to take animagus form. He's almost fully transformed!" James shouted.
"I DON'T BLOODY KNOW HOW, JAMES!" Now Remus had tears running down his face. This was too much for him. James took on stag form.
Sirius was completely transformed physically, but Remus knew it usually took about 5 minutes for the wolf to take over his mind after his body had transformed.
The wolf stared at Remus. Its face looked terrified. It was still Sirius in there.
"Sirius please. Just hold on. Don't get it take over. FIGHT!"
The wolf growled and shook its head. When it looked back up, its fangs were bared. Sirius has lost. The wolf bent down and pounced onto Remus.
Now Remus was the one terrified. All he could hear was a ringing in his ear. He was going to be killed by his own body, while inside his best friend's body. He closed his eyes and awaited the bite.
But it didn't come.
The pressure of the wolf's claws was lifted off of his shoulders. Remus opened one eye to see a bright white light flying above him. A phoenix patronus. He turned to look at the door. Dumbledore raised his wand and circled it around his head. He shouted something incoherent, and Remus blacked out.