Severus was making his rounds when, out of the corner of his eye, he spotted a big, black dog trotting alone. He narrowed his eyes, he'd recognise that dog anywhere.

Severus strode over to the dog, crossing his arms and tapping his foot. The dog slowly changed in a man, paws lengthening into fingers and feet, and shaggy black hair receding until an unkempt, lanky man sat hunched over at Severus's feet. Thankfully, no students were around to witness this. Sirius Black slowly rose to his feet.

"Black," Severus growled. "What are you doing outside the Room of Requirement? You could have been seen by a student. Dumbledore will have your head if he catches you out here." He grabbed Sirius by the upper arm and pulled him into an empty corridor.

"Relax, Snivellus," The nickname caused Severus to straighten his spine and regard Sirius coldly. "I was a big black dog." Sirius chuckled. "Most students wouldn't spare me a second glance, let alone recognise an animagus. I was completely incognito."

Severus rolled his eyes and crossed his arms, annoyed. "What are you doing out here anyway?"

"Well now I'm embarrassed to say."

Severus narrowed his eyes. "Tell me or I swear to Merlin, I'll-"

"Relax. Geez. Don't get your knickers in a twist." He held out a moist, yellow tennis ball. "One of the kids threw it too far and it went out the door. I was simply retrieving it."

"You mean to tell me that while Dumbledore risks everything to hide you here, putting students and innocent families in danger, you're playing fetch?" His tone was incredulous with a hint of disdain.

Sirius shuffled his feet, his eyes at the floor. "These kids have lost everything. I was just getting their toy back."

"How did it get out the door anyway? The door is only supposed to be opened upon hearing the password."

Sirius shrugged. "Some of the students come and go, visiting their families."

"That isn't allowed!"

"Relax Snape. They're careful not to be seen. It's not hurting anything."

"Your godson is among the students you put at risk every time you allow this."

Sirius's eyes widened. "Harry is at Hogwarts? I want to see him."

"Out of the question. You are a wanted man. The fewer who know of your presence, the better. Potter doesn't even know who you are."

"I don't care. I want to see him."

Severus shook his head. "It's just not possible right now. You need to return to the room and stay there."

Sirius plunged a hand through his thick, black hair. "If I write him a letter, can you get it to him?"

"No. Absolutely not."

"Snape, this is important. He's my family."

"He doesn't even know you exist."

Sirius puffed out his chest. "I'm his godfather. Surely he's heard of me."

Severus rolled his eyes. "I sincerely doubt it. He was raised by muggles who treat the word wizard like it's the plague."

"He should have been raised by me." Sirius's tone was grim and there was a determined look in his eyes Severus hadn't seen before. For the first time, Severus saw the desperate man before him and not the idiot teenage who'd tortured him relentlessly.

"Enough of this. Return to the room and do not let me catch you roaming again. I'm serious, Black. I should report you to Dumbledore for this." Severus crossed his arms.

"Please don't. I'll stay in the room, I swear to Merlin."

Severus sighed, relenting. "Fine. But if it happens again, I will tell him. Dumbledore is putting a lot of faith in your just allowing you to take refuge in the castle."

"I understand, and believe me, I'm grateful. I won;t leave again Snape. I promise."

The sky darkened suddenly, as if a storm had magically appeared overhead. The corridor became dim as the light from the windows was taken away and Severus and Sirius both looked up, alarmed. A eerily familiar voice sounded, booming all around them, so loud, it almost hurt.

"Where is the traitor, Sirius Black?"

A chill ran down Severus's spine and he urged Sirius along to the Room. Severus recognised that voice. It was the voice of the Dark Lord. Soon, they had both broken into a run. Students ran through the corridors, the voice causing pandemonium. No one noticed the two men running alongside them. Severus struggled to keep a grip on Sirius's sleeve. He didn't trust Black to return to the room instead of going to search for Harry. Together they shoved through the students and past the formidable figure of Minerva McGonagall, who barely spared them a second glance.

Minerva stood in the middle of one of the corridors, shouting at the top of her lungs for students to return to their common rooms. Severus reached the Room and whispered the password but the door remained shut. He tugged the handle but the door remained sealed. He cursed under his breath as the door slowly began to fade away at the edges. Soon, it was gone, both men left staring at an empty wall.

Severus hissed through his teeth. This was all Black's fault. "We'll go to Dumbledore's office," Severus said, tugging him along.

He led Black through the panicked students. Once he reached the entrance to Dumbledore's office, he turned back, only then noticing that Sirius had slipped out of his grasp. He retraced his steps, shoving through the crowd of students. "Damn him," he muttered to himself. The corridors were slowly starting to empty as the students returned to their common rooms. Up ahead, Severus spotted Sirius on his knees, face to face with a small, dark-haired boy, the spitting image of his father.

Severus lowly uttered every curse he knew, grabbing both Sirius, and the boy and steering them to the office. He shouted the password and nearly threw them both into the appearing passageway. "I am the head of Slytherin, I must go make sure all my students are accounted for. Stay in the office until I or Dumbledore return. Do not touch anything."

He left them against his better judgement and headed down into the dungeons. There were still a few students remaining, rushing on their way to their common rooms. Severus stepped aside to avoid a blonde Ravenclaw, coming hard into contact with a stone witch. He groaned, clutching his chest, and the witch slowly moved aside to reveal a hidden passageway. The sound of stone grating against the stone floor was almost excruciating and it was a wonder it didn't draw the attention of the few remaining students.

Severus prided himself on knowing every nook and cranny of the school. He had spent many a lazy afternoon exploring the castle, learning every secret within its walls. But the passageway the stone witch had revealed to him was dark and unfamiliar. He slowly stepped inside and the stone slid back into place. He shivered, finding the passageway dank and chilly. He could hear water dripping, and if he'd had a light, he felt certain he would be able to see his breath. Severus was now encased in darkness and he took a few hesitant steps forward. Something solid caught his foot and sent him sprawling on the ground, causing him to cry out. He reached for his wand and cursed before whispering "Lumos". From the pain radiating from his ankle was definitely twisted, maybe even broken. In the darkness, a pale white hand extended towards him. Severus took it and slowly followed it up to its owner, finding himself looking up into the startling green eyes of Lily Potter.