A/N: Hello all. It's been a long time since I've posted anything, especially a new story so I'm a bit rusty. Just wanted to say that I hope you enjoy. It's my first Harry Potter fic and I'm trying out my version of one of my favorite old ideas. Hope you will stick around with me for the journey. Enjoy and don't forget to review to let me know what you think! Specials thanks to deliriousdays, my wonderful beta!

Disclaimer: I do not own Harry Potter or the magical world created by J.K. Rowling. I just play around with the characters.

Chapter 1: I Solemnly Swear

The man hurried along the street, avoiding the light cast by the street lamp and in turn blending into every other shadow. With his cloak tight around him, he kept glancing back at number four Privet Drive, the house that with each step he took, he was slowly leaving behind.

He wore a sour expression as he neared his destination just a few houses down from number four. It was far, but not far enough that he couldn't escape the feeling that as he moved further away he was leaving something behind; something important.

He shook the thoughts from his head, his black eyes no longer flickering back to number four; instead they focused intently on the house he was heading to.

Unlike all of the other houses on the quiet Surrey street, this house was completely dark, devoid of any light, not even the outside light by the door was on. This little deviation from normalcy must be what unsettled the muggles around, the man mused, thinking about what Arabella Figg had told the headmaster. How curious it was that people would avoid a house simply because of the absence of a light.

He couldn't understand muggles.

Rapping on the door twice, he waited patiently, careful not to look around or act suspiciously. He heard shuffling and a voice muttering what he could only guess was a slew of swears before the door was wrenched open with an ear-splitting creak.

A man stood in the doorway, his dark hair messy and his face unshaven, "Oh it's you, Snivellus," the man said with a hint of distaste behind his words.

Severus Snape sneered at the demeaning name he had been called relentlessly during his youth by the very man in front of him. Some things never change.

Sirius stepped to the side rather clumsily, allowing his visitor into his none-too-welcoming abode.

The inside was as dark as outside and in one swift motion, Severus drew his wand. With a flick of his wrist light flooded into the room.

"Ugh, must you?"

"I take little pleasure in being able to see you fully either, Black, but if we are going to continue these visits I'd much rather be able to do it in the light."

Sirius turned to face him and Severus could see that the other wizard's eyes were glossy and red, either from having not been sleeping or from too much firewhiskey.

He assumed both were correct, "You look like rubbish." Black told him.

"I can say the same for you. Now are we going to stand here in your foyer all day or are you going to invite me in?"

Sirius rolled his eyes. "Yeah, come bloody well in."

Severus followed after Sirius as he made his way to the kitchen, not being able to hold back a sharp remark on the way, "I've had Death Eaters show me more hospitality."

Sirius gave him a bland look over his shoulder, clearly not amused with Severus' statement.

They walked past an empty room on their way to the kitchen. After eleven years it was still as bare as when they had viewed it together before Sirius made the purchase.

"Pity that the Black fortune couldn't be put to use buying you better furnishings."

Sirius' eyes swept over the room, where bits of dust had collected along the edges of the hard wood, "Not much use for a living room."

"I thought you had set an idea that you'd make it as presentable as possible in case the boy came to live here."

Black grunted but didn't say anything, a testament to whatever bad mood he was in and entered the kitchen, this better furnished, with some ancient muggle appliances and a sturdy wood table off to the side with a few chairs.

"I suppose I should offer you something. Tea, perhaps? Firewhiskey?" At this he held up a bottle that he could see was a quarter of the way full.

It was firewhiskey then, too much of it. The man was inebriated and there really was only one time of the year that he had seen him as such and that was a few months away.

Something must be wrong.

He frowned, not sure why he cared, and wondered if his talk with Albus had something to do with it.

"You have a common purpose now, Severus. It's much different from when you were fifth years. I wouldn't be so bold to say your hatred has diminished completely but that it simply gave way to a mutual understanding."

He remembered how he had flinched at the thought but had sobered up completely. It was true, even if he would rather suffer the Cruciatus Curse than admit it to Black.

"Did you hear me Snape?" Sirius asked and for a brief second, his wild gaze meeting Severus', "I asked if you heard anything from Arabella?"

"And you have not?"

Sirius sat back in his chair, hand leaving the firewhiskey and settling on his lap, "I don't really talk to her."

"Not unless you're masquerading as Padfoot you mean?"

Black's expression darkened after a brief moment of surprise crossed his features, "I don't know-"

"Oh don't be daft, Sirius. We are not all as empty headed as you," Severus spat, "Peter Pettigrew managing to become an Animagus at fifteen by himself?" he scoffed at such an outrageous idea, "Highly doubtful. He had to have help and since he was always trailing after you and Potter I'm certain that meant that you are an Animagus too."

At the mere mention of the rat named Peter Pettigrew, Sirius' face took on a heated look before he let out a long breath as if expelling any anger inside of him and gave Severus a challenging look as if to say 'Yeah and so what?'

"I've not been over to Mrs. Figg's house in some days because she hasn't been home and I was wondering if there was any news." said Sirius.

The headmaster had not said anything to him at their meeting earlier even when Severus had commented about the incoming first years, "Nothing that I know of, but I do expect that Albus would like to meet with the both of us soon enough to discuss…" he trailed off.

He had taken to calling him Potter or the boy in Black's presence just to get a rise out of the other man but he was never that in Severus' head; could never really be that either. From the moment he laid eyes on the bundle in Lily's arms, he was always Harry, even if he tried to fool himself while speaking out loud.

"Harry," Sirius breathed, saving Severus the pressure of deciding what to call him.

Sirius' eyes lit up for a moment as they always did when the conversation turned to his godson and the effect left him looking more drunk than before.

He grabbed for the bottle before him and took a long pull, slamming it down when he was done, "Those bloody muggles are keeping his letters from him, you know."

Severus felt his eyebrows come together. "What do you mean?"

"Owls have surrounded the place. Didn't you notice or are they gone by now? They only do that if you've purposely ignored a Hogwarts letter." When Severus didn't reply quickly enough Black continued, "Petunia and that oaf of a husband hate magic and they are determined to keep Harry away from it, from us." The glassy eyed gaze he gave was definitely not caused from the drinking now but from sadness and anger, "You remember Petunia, Snape."

Ah yes, how could he forget Lily's sister? How could he also forget that Black had access to his Pensieve where the memory in which he had first met Lily and Petunia Evans was stored?

"Dumbledore will see to it that Harry receives his letter." Severus finally said after a long moment of silence.

Severus would also have to have a few words again to the older man about the living arrangement Harry was given but again that wouldn't come to any good conclusions, just as it had eleven years before.

"Don't you think that it would be better if we just-" Sirius started but was interrupted by Severus.

"We will do nothing of the sort."

"WHY NOT?" Sirius was out of his chair now and a bit unsteady on his feet, "I'm his godfather! Lily and James wanted me to take care of him, not those damn muggles!"

"And you forget where I factor into this do you Black?"

"How could I?" Sirius sneered, "I know all about your responsibilities, but I don't see you doing anything!"

Severus too was on his feet now, "You don't think I would rather him be here? Unlike you, though, I am not selfish. I know what the best for him is."

Both men had their wands out and at each other's throats in an instant. Their eyes were daring each other to make the first move, to cast the first curse, but neither did.

Severus closed his eyes briefly, "I did not come here to duel you, Black."

Sirius gave a low chuckle and lowered his wand, "Much rather you had."

Severus put away his wand, "Anything else you wish to get off your mind?" He drawled.

"Don't supposed Albus would let me give Harry an anonymous birthday present?"

A small, very slight smile, worked its way onto Severus' mouth. Eleven was a big year but no doubt the Headmaster would advise against them giving anything to him, not yet anyway.

Sirius' shoulders fell and for a minute he truly did look like a lost mutt, "I guess I know the answer."

He didn't know what else to say so he turned around and walked back to the foyer, toward the stairwell.

"I'll leave you to your memories," Severus could hear Black say morosely as he climbed the stairs.

A quick Lumos charm revealed more empty dusty rooms, save for the one that Sirius occupied that held a bed and some other belongings. Severus didn't know exactly since he was never around really to get a good look.

The third room and last bedroom were more to the corner and probably had the most in it in the entire house. He and Sirius hadn't touched much since the last time the room was occupied. The makeshift cot still sat in the middle of the room, with whatever they thought they could salvage out of the wreck of the Potter's home.

He took a deep breath before entering and strode over to the little alcove where a Pensieve sat tucked for safe keeping. The stone structure was covered with runes all around the base and lead around to the bowl on top that was filled with the silver swirling memories of not only himself but Sirius as well.

"I cannot believe you spent your inheritance gold on that," he had said when Black levitated the huge Pensieve into the room. He couldn't believe why it was necessary.

"You don't think Harry should have an account of these things? Doesn't he have a right too?"

"You don't need a Pensieve to tell a child something, Black."

"We cannot tell it all. Besides, Dumbledore suggested it; he thought it might be good if anyone ever questions the-well you know."

Severus snapped out of his reverie. What memory did he want to relive today? What kind of masochistic thoughts did he want to endure? He was sure that Sirius came up here when he was just as depressed and when firewhiskey just wasn't cutting it.

He chose the memory from June 1981, one of the earliest memories among the collection. He leaned his head into the bowl and let himself fall into the memory.

The first thing he was aware of, like he was that day, was how it smelled. There was the distinct fresh smell of flowers, honeysuckle and other scents, that carried pleasantly on the breeze. He watched himself stare at the garden, still beautiful in the memory and bursting with colors. He was not aware that someone had come up to the side of him and was watching his past self take in the view of the magnificent garden.

"It's all I can really do now," Lily Potter said, startling him into whirling around to face her. He saw himself relax and soften when he registered who it was.

He came in closer so that he was only a foot or two away from himself and Lily. She was so real. And that was the danger of the Penseive. He could stand here forever and watch her from his memories and if it wasn't for what was about to transpire here and what he had promised, he would.

Lovely Lily Slughorn used to call her. And he was right. She glowed in a summer sun dress, long red hair flowing down her back, face spread out in a wide smile at the sight of him. One that hadn't been directed his way in a long time, he remembered, "Hello Sev," she greeted his younger self, as if they were back at Hogwarts and meeting to study for a potions exam.

"Lily," he had said and he remembered not knowing quite what to do. The owl had found him in his Spinner's End home requesting his presence at the Potter's home. They hadn't talked since Graduation, why had she reached out to him now?

She rubbed her hands together and nodded toward the door, "Would you like to come in?"

He had nodded vaguely, still unsure and followed her into the house.

Every time he visited this memory, he was shocked by how whole and together the house was. He expected to find it as he and Sirius had, broken with pieces of the ceiling collapsed onto the floor and everything strewn about, but it was tidy and comfortable, if he at the time found many things that way.

Lily led him to the living room, where the hardwood floors were covered with a rug. There were bookshelves built into the wall around a stone fireplace. On the mantel were pictures. He noticed the one of the Order beside one of the Potter's wedding.

"Can I get you anything?" she asked, "I've made some lemonade."

"I'm fine, thank you."

They stood awkwardly and Severus smiled at himself. Now, years after this memory had taken place, he could look back and see things he had missed. He saw how Lily kept playing with her hands and never stopped moving. She had been nervous.

Finally she took a seat on the small couch in one of the corners, across from two armchairs. He sat down as well, eyes never leaving her.

"How are you?" she asked and again he smiled, remembering how awkward it all seemed.

"I'm-" he hadn't known how to answer the question. Miserable hadn't seemed appropriate since he knew he had chosen to work for the order and serve the Dark Lord. Fine wasn't acceptable either, because in those terrible times, no one was really fine.

She smiled a bit, "Stupid question, I know." she moved a hand to push a piece of hair behind her ear but thought better of it.

"How are you?" he asked, having nothing better to say.

She pursed her lips and she avoided his eyes. "I've been meaning to talk to you at the meetings. I-I don't think it was right how we left it. We were young and well I see what you're doing now for us, for the Order and I wanted to thank you."

He remembered not knowing how to respond. He wanted to be angry because that was what she had asked him to come for? She couldn't have stopped him one of the times he was at an Order meeting? And he remembered feeling relieved because if it was as simple as that, he had nothing to worry about.

"You're welcome." Was all he could manage. He certainly did not deserve thanks. There were half bloods and muggleborns who would certainly not thank him for what he had done but he didn't and couldn't mention that.

Before either could say anything else, the door opened and Severus knew instantly who it would be. He was up on his feet before James could enter the room and was prepared to leave the instant the man has spotted him.

But there was none of the old animosity on his face, no mischief playing on his features. He nodded once, "Severus," and then continued around to Lily where she stood and they embraced. He kissed her on the forehead and then sat down, one hand briefly touching her stomach before letting it drop to his side.

Severus had been in shock. He had thought that Lily might want to see him, but both Potters? What for?

Lily considered him for a moment longer and bit her lip, then turned to look at her husband, who looked just as unsure, but nodded anyway, encouraging her to continue.

"A few days ago Dumbledore told us about the prophecy." The way Lily said it had broken his heart. She knew that he knew and what he had done with that information.

"I-" he had started.

"We know what you did We also know that you urged Dumbledore to have us go into hiding and we're going to do that but because you are now a spy," James smiled at the word, "We thought that you might be able to help us with something."

"Help you? With what?"

At the time, everything had moved incredibly fast and he had not been able to take in as much as he would have before. But now as he stood feet away like he had done many times before and observed the scene objectively, he could notice that James was just as nervous as his wife. Years ago this would have made him smile. The great James Potter was nervous about something he needed Serverus' help on? That was just too rich. But now, years later and as James' memory began more and more distant, he could understand just a little better.

He sighed to himself. You've made me soft ghost.

James took Lily's hand at his side. He imagined that he gave it a tight reassuring squeeze so that she could continue. He also knew that his past self was growing impatient and anxious. He all but wanted to demand what they wanted out of him so he could get it over with.

"We wanted to perform a Geminus hereditas ritual in case well in case we didn't make it." Lily said and braved looking into his past self's eyes.

"What?" he asked, rather dimly. It was the only reaction he seemed to be able to mutter and every time he viewed this memory he had the sudden urge to slap himself on the back of the head.

"It's a ritual that creates another parent for the child, usually done when-"

"I know what it is Potter!" he said sharply, snapping out of whatever fog had come over him a minute before. He turned to Lily and from where he stood he could see the other self's face soften as he met her eyes again, "Why me?"

Lily smiled, another smile he remembered from their early days at Hogwarts. "I know you, Severus. And I believe you may be able to help save our son."

To this day chills came over him when she said our son. As if she already knew what his decision would be.

"But I'm a-"

"Death Eater?" James said sourly, "Dumbledore assures us you know what side you belong too."

He remembered his mind was flashing with the great number of flaws in the plan but for some reason, a reason that baffled him today, he could not say no.

"I understand it's a bit of a shock and I'm sorry. You can say no but will you at least consider it? We don't have much time but James and I can leave you alone for a bit. It's just we're a little short on time." At that she gave a short laugh and looked down at her protruding belly.

What he knew of Geminus hereditas back then was very limited. It was old magic, blood magic that wasn't used that often. It was big during early wizarding wars when husbands left their pregnant wives for battle and never came home. Another man would have the charm performed on him and the child would effectively also become his.

Lily placed a hand on his arm briefly before continuing out of the living room and James followed.

He never knew how long elapsed between that moment and when James Potter came back in. He just knew he had been sitting in the chair, staring at the picture of the Order and going the idea over and over in his head.

James cleared his throat and took the seat he had last vacated. For what seemed like hours neither said anything.

"You want me to be a father to your child?" Severus said his eyebrow raised at the once Quidditch star.

The other man thought over it for a moment, "No. I don't think anyone really wants to share their child. But I love my child and I don't even know him yet. I know that I would do anything for him and with this prophecy…" he sighed as if he were old and at the end of his life, which Severus now realized was partially true, "Voldemort is after us and we have our own protections in place but it may not be enough. We need all the help we can get and if that means that you have to do this, then I can accept that."

"Why not someone else? Black?"

"He's already Harry's Godfather. We need him to have a Godfather. And this is different."

"Harry?" he heard himself question.

James smile. "Lily likes it."

He remembered getting angry after that. How could this stupid man, how could Lily believe that he could be any good at this?

James looked him in the eyes then, something he was sure he never wanted to do, 'I know how you feel about her. I just wonder if you're able to love her child too."

There was no groveling, no pleading. James made his case, calmly. He didn't tell Severus to back off, or get territorial like Severus always assumed he would if he ever found out the truth. James was talking like an adult and he was asking and reasoning.

Severus remembered something pulling at him, something positive. He remembered feeling lightness, a happiness of sorts. He didn't know why, maybe it was as James had said and his love for Lily was influencing him but a few minutes later when Lily joined them with cups of tea, he agreed.

The ritual was rather medieval. It required blood taken from a blessed silver blade and an oath in Latin. They repeated it in English too, just to be sure.

When they were done James Potter had the audacity to grin at him. "Congratulations, you're a father."

He pulled out of the memory soon after, the sick feeling in his stomach that always accompanied the end of the memory settling as he came back to the present.

Harry had been born a month later and the Potter's had been killed a year and three months after that, leaving him a single parent.

He took a seat in the rocking chair that Sirius had also bought with his inheritance money eleven years ago and tried to calm his thoughts. How good was the oath he took if he hadn't seen his son in eleven years? His own son was living with his muggle relatives who hated him because he couldn't convince Dumbledore that it would be safer if the boy came to live with him and Sirius.

The Geminus hereditas had made his blood apart of Harry's and had made the boy legally Severus' as well as James' and Lily's but it hadn't made him feel like a father.

He had actually never intended to form a bond with the baby. As far as he was concerned he was a back up, and the more he thought about it the more it proved to be true. He was a last resort and one that would surely be forgotten as Harry grew up.

A little whistle, decibels lower than the caterwauling charm but just as effective reverberated throughout the home and made Snape get up out of his chair before his mind could even register.

"Snape!" Sirius yelled from downstairs and Severus apparated to the kitchen in an instant.

"The alarm. Harry's left Privet Drive." Black's eyes were wild and his face drawn and pale. He was sobered completely from before and he grabbed his wand that was lying next to the empty bottle of firewhiskey. Before he could move another inch and owl dropped a letter on the table.

It read in Dumbledore's delicate scrawl: Harry's safe. Floo to my office.

Sirius closed his eyes and his body relaxed a little. Severus breathed in deep, realizing somehow he had been holding his breath.

"This better be good," Black said over his shoulder and went to the living room where the fireplace was.

Severus whispered "Nox" and all of the light vanished from the house except for the green jet of flames that appeared after Sirius threw the floo powder down and said his destination.

It had begun to rain as Severus followed into the fireplace. He wondered fleetingly what kind of portents the rain could bring.

ETA: Thanks so much to Alex, for catching something I had missed.