Prologue

The canopy of the bed held no secrets. Its heavy brocade much as the solid wooden furniture had been made for eternity and therefore remained unfazed by insignificant events such as death. Yet it was a safe spot to look at, Harry decided, precisely because it gave nothing away about the room's former inhabitant. Unlike the room, the muggle posters had withstood the test of time, because of the permanent sticking charm a rebellious teenager had once used to drive his mother insane. Well done at that, Harry thought glumly.

Everything about the room reeked of misery and claustrophobia - and Harry knew a little something about claustrophobia - from the unmade bed to the half empty bottle of Scotch collecting dust. He had not allowed anyone to clean in here or change anything about the way his godfather had left it - the way Sirius had left it, Harry reminded himself. It was no use trying to avoid the name and it was definitely no good lying here staring at the canopy.

With a sigh he got up and rubbed his aching back; lying still for a long time hurts.

He was about to move toward the door and brave the day when a movement caught his eye. His gaze turned toward the mess on the desk.

Among a bundle of documents there was an old photograph. Harry hesitated, not sure he was ready to look at old pictures of his godfather. However, something about that singular picture among a pile of old correspondence intrigued him. He stepped closer.

It was the image of a teenage girl turning reluctantly toward the camera. Harry had never seen her before. He turned it around but all it stated on the backside was the year, 1976. The picture was well-worn and had a yellow tinge, which was weird. Magical photographs were far more robust than their muggle counterparts.

Upon closer inspection Harry was fairly sure it had been taken on the Hogwarts grounds even though the girl wasn't wearing a school uniform. She looked rather unhealthy, Harry decided. Black hair framed a pale face and the muggle clothes were too big for her. What was remarkable about her though was the way her face lit up when she smiled.

Harry smirked. Well done, Padfoot.

Of course he wouldn't have known about his godfather's past girlfriends, he had never thought to ask about that aspect of Sirius' youth. There were way too many things he should have asked, when he had still had time. Harry's eyes started to burn. Don't even go there, Potter, he reminded himself. As he was about to put the picture back where he had found them, his gaze fell on the parchments underneath. They were letters. Dozens of them.

A paragraph in verse caught his eye.

But could youth last, and love still breed,

had joys no date, nor age no need...

Whether this will ever reach you I don't know for it has been a long time since you'd last looked at me in recognition and as of now I have no hope this injustice will ever be righted. However, I will give my last breath to try.

Farewell.

Io

Harry turned the letter around looking for the date and found it at the top: May 5th, 1988. But... that was after the war, Sirius must have been imprisoned for years. Transfixed he stared down at the slanted writing as his mind raced. That was just impossible. His eyes moved back to the blue eyed girl. Who are you? he thought.

Who are you and why have I never heard of you before?

A knock on the door roused Remus from his thoughts.

He had been staring at the same page of 'Dreadful Denizens of the Deep' for who knows how long, when he looked up to find Harry standing in the doorway.

"Harry," Remus put his book down and motioned to the other chair in front of the fireplace, "Do come in." He noticed the dark bags under Harry's eyes and scolded himself for not taking better care of James' son. It was painful to be back at Grimmauld Place but that was no excuse.

Harry looked around the living room as he sat down. He hadn't spent much time here ever since...that summer. The room seemed strangely foreign to him now that... Don't think about that, he told himself again. "I've found something," he blurted out instead. Remus raised a brow and waited for him to elaborate.

"Do you know someone named Io?"

Remus froze. Merlin. That was not one conversation he was ready for.

"There were some letters, and I've found this picture... "Harry took the photograph out of his back pocket when he caught the expression on Remus' face. "What's wrong?"

Remus shook his head numbly. "I haven't heard that name in a long time. Yes, I knew her. She was in our year in Hogwarts."

"Why haven't I ever heard of her? It seems like she was err- a friend?"

The grimace on Remus' face was nothing short of pained.

"So she died?" Harry tested. The chagrin on the Remus' face deepened as a terrible suspicion turned Harry's stomach. "She was a Death Eater?"

"No, nothing like that," Remus replied quietly as he motioned for Harry to show him the picture.

"But she wasn't in the Order either, right? Or else I would have seen her before."

He handed over the photograph.

"Ionia was mainly for herself and loyal to few. In that way she was a real Slytherin."

Harry started, "I didn't know Sirius had friends in Slytherin."

Remus smiled at the look of astonishment on Harry's face as he replied. "Only the one."

His weary eyes turned to contemplate the yellowed picture of the girl he once knew. She was trying to hide behind a curtain of black hair but when she turned to the camera a reluctant smile appeared. Had Sirius taken it? Remus felt the pang of an old regret added to the grief of his recent loss.

He put the photo down, suddenly feeling exhausted. "Fiercely loyal," he muttered, as if to himself.

"What happened to her?" Harry searched the other man's face, wondering. "There was a farewell note..."

"Remus?" he prodded.

Remus reluctantly returned his gaze. "That's a really long story, Harry..." he raised a hand defensively as the young man was about to protest, "And not a nice one at that. Most people in it don't get away too well, you might not even-"

"I might not even want to hear it?" Harry replied indignantly.

"There are things you might not want to know about how we all were back then. War - it has its way of getting into your head, fills you with doubt and suspicion. It brings out the worst in everyone, Harry. "

"You don't get it, do you? I don't care if it's pleasant! I— ".

His sudden anger had subsided as fast as it had appeared.

"I don't even know if he took his bloody tea with sugar, much less of a mysterious Slytherin friend who'd sent him countless letters for years - I mean, was he in love with her?"

As he spoke treacherous tears started to gather in his eyes. Harry wiped at them angrily.

"I thought I'd have time to ask him about all of that, that there was time." Harry stared blankly at the fire in front of them.

Remus wanted to reach out to console him but stopped his hand in mid-air, unsure how. With a sigh he finally settled back into his chair.

It would be a long night.

"Well, for one thing, you wouldn't have seen her in any of your parents' pictures because "Jo" couldn't stand your father."

Harry raised a brow at that. Hadn't his father and Sirius been inseparable?

Then he tried to imagine Ron strike up a friendship with Millicent Bulstrode. Harry shuddered.

Remus shrugged. "The feeling was mutual."

"Also she didn't join us until fifth year." Remus grinned, "I'll always remember her first day though."

Harry raised a brow. "Why?"

Remus grin widened.

"Because it was the day Sirius Black met his match."

Both the title "When Rivers Rage and Rocks Grow Cold" and the two lines in verse are quotes from the poem "The Nymphs Reply to the Shepherd" by Sir Walter Raleigh.

Update: Now with proper Grammar and Spelling ;) All the Love to my wonderful Beta reader MissMooToYou! All remaining errors are my own.