If...

Severus had returned home as proud as a peacock, with the satisfying feeling of a mission accomplished. He had Slughorn in his web, and now all that remained was to manipulate the old professor into revealing the information he so desperately needed.

But his good humour did not last.

No sooner had he entered the sitting room than Lily's son, delighted at his return, called out "Daddy!" in a happy and clear voice, while Remus Lupin tried to entertain the child with a puppet show.

At the boy's words, the werewolf froze and turned to Severus with a look of silent reproach. Humiliated, Severus was about to play the 'babbling nonsense' card, hoping to extricate himself from this disastrous situation, when the child - completely unaware of the mire he'd plunged himself into - repeated the feat in full view of Lily, who had just entered.

The young woman, clearly uncomfortable, pinched the bridge of her nose as if trying to hold back a sneeze.

A heavy silence fell. No one dared break it.

Harry, who had been sitting on the carpet next to Lupin, crawled over to Severus and tugged at his cloak - presumably to be picked up.

"Daddy?"

Severus had half a mind to tell the brat to be quiet, maybe even cast a Silencing Charm, but the damage had already been done. Lupin wasn't deaf, and he'd no doubt noticed that Harry's pronunciation and vocabulary had improved considerably.

"Would you like to explain?" asked Lupin in a carefully measured tone.

"Well... how shall I put this..." Lily began awkwardly. "Harry has taken to calling Severus that, without us really knowing why..."

The boy tugged at the dark cloak once more, and Severus - irritated by the habit - shot Harry a sharp look. But, faced with the child's pleading eyes and quivering lower lip, the young man relented and scooped him up, avoiding a tantrum.

"I never meant for him to call me that," Severus said coolly.

For a few moments Lupin watched him with an unreadable expression.

"If Sirius finds out, he'll probably try to kill you," the werewolf said with a wry grin. "But don't worry, Severus - he won't hear it from me."

Lupin rose and approached Severus.

"And as for you," he said to Harry, "if I were you, I'd wait a bit before calling Severus 'Daddy' in front of Sirius. You don't want to get Severus into trouble, do you?"

The baby giggled - a soft, pleasant sound that reassured Severus somewhat.

Lily, probably fearing a full-blown argument, offered to make some tea. Severus had no objections: Lupin was far more tolerable than Black, even if he was a werewolf. Caution, however, remained prudent.

"So... how are your lessons going?" asked Lupin, a teacup in his hands.

"Fine," replied Severus, glancing at Harry, who was playing on the carpet. "Where have his blocks gone?"

"I've taken them away for now," Lily announced. "He built another tower that was way too high, and it fell..."

Severus did not need any further explanation. The day before, Harry had built a precarious tower that had collapsed with a crash. The child had burst into tears, distraught at the disaster he'd brought upon himself.

"I told Lily I'd bring him some new toys," Lupin added.

What on earth could the werewolf bring? Severus had no desire to see the boy flying around the living room on a toy broomstick - especially as the back garden was a veritable junkyard, hardly safe for a toddler.

"Don't worry, I'm not planning on bringing a broomstick," Lupin reassured him. "But I won't be able to stop Sirius if he decides to."

Black was Severus' problem.

"I'll go to a Muggle shop," Lupin continued. "There's one in the town where my parents live."

"That would be lovely," Lily said, watching her son lovingly as he played with a teddy bear. "And don't worry, I'll pay you back as soon as it's safe for me to get to Gringotts."

Lupin protested, claiming he could still afford to buy toys for the son of his two best friends. This detail piqued Severus' interest - was Lupin poor? Potter had been a spoilt prince, and Black was heir to one of the most prestigious families in the land. As for Lupin and Pettigrew, Severus had no idea. He'd never cared about their pedigrees or their parents' vaults, but he was well aware that, unlike himself, they weren't pure-bloods.

And Lupin, of course, was a werewolf. People of his kind struggled to make ends meet.

Severus exchanged few words with Lupin, who seemed more interested in his conversation with Lily. Of the Marauders, Lupin was the least obnoxious, and at least he had the decency to obey Severus' household rules. Still, he remained a werewolf - a creature that had almost cost him his life.

Over time, Severus had become less certain that Lupin had knowingly participated in this terrible prank orchestrated by his so-called friends, but he still couldn't bring himself to trust him completely. After all, who knew what went on in the twisted minds of such monsters?

This distrust had its roots in the books he'd read as a child. In an old grimoire once belonging to his mother, Severus had found horrifying tales of lycanthropes. Eileen Snape, seeing the kind of literature her son was devouring, had confiscated it - not because its contents were inappropriate for a boy of Severus's age, but for fear of incurring the wrath of Tobias Snape, his Muggle father, who despised anything remotely magical.

The book was probably still in the attic somewhere, but in retrospect Severus saw it for what it was: a collection of prejudices, more harmful than informative. Werewolves, for example, did not eat raw animal entrails at every meal except on full moons.

Severus, whose favourite pastime at Hogwarts had been watching Lupin's every move, was well placed to dispel this myth - although he had noticed a preference for rare meat.

"All right, Sev?" Lily asked gently. "You looked miles away."

Severus jumped slightly, noticing Lupin watching him with faint amusement. He didn't like it one bit, but thought it wiser not to show his irritation. Lupin now had enough ammunition to cause real chaos.

"I was just thinking about my lessons," Severus lied.

"You must be terribly busy," Lupin suggested.

Severus merely nodded. He had no desire to discuss his work with the werewolf - or the mission Dumbledore had entrusted to him. Lily was the only one he really enjoyed talking to.

Lupin left a short time later, but Severus knew he would see him again during the week. It was a necessary evil - one that spared him the displeasure of running into Black twice a day.

Once Lupin was gone, Lily couldn't resist the urge to ask Severus how his plan was going. He himself was dying to tell her how clever and brilliant he had been - a true strategist.

But Harry had other ideas and once again demanded Severus' attention. The young man, reluctant to be interrupted by tears, pulled Harry close to his chest.

"He missed you today," Lily said, stroking the child's black hair. "He even called for you when he knocked over his tower of blocks."

Severus looked down at Harry, who was curled up against him, comfort blanket in hand.

"So you thought you were an extreme architect again, did you?"

The little boy said nothing, just buried his face in Severus' shoulder. The gesture made Severus smile and he launched into the story of how he'd spent the morning laying his trap. Lily listened intently, admiration gleaming in her eyes.

"I wish I could send him a message," Lily muttered regretfully. "But it's better he doesn't know where I'm hiding..."

"It's for the best," Severus agreed. "He's still in contact with Barnabas Cuffe, the editor of the Daily Prophet. You know how journalists are - always digging, spinning stories out of thin air... In fact, I read today that the paper believes you and Harry are in America... in Iowa."

"Iowa?!" Lily repeated, almost laughing. "I hardly know where that is!"

"The middle of nowhere," Severus said with a grin.

"I sometimes wonder how they manage to come up with all this nonsense..." 

"The Order is in contact with some freelance writers and journalists... From time to time they feed them false information to keep them busy. The Daily Prophet doesn't care much for the truth, as long as it sells." 

"Any new arrests? Remus didn't get to read the paper this morning... The owl was late." 

"Not one... So they're..."

"Making things up," Lily finished with a faint smile. "By the way... I need to talk to you." 

For the briefest of moments, a hundred thoughts raced through Severus' mind. Lily and Harry were moving in with Lupin - or worse, Black. They'd gone behind his back and Dumbledore had approved it. Or maybe Lily and Harry were about to move to Iowa, since no one would take that absurd Daily Prophet article seriously anyway. 

"I've started working upstairs," Lily continued.

She didn't leave. 

"The bathroom's as good as new - well, almost. We'll have to get some new towels and a few things to brighten it up, but it doesn't look like it used to." 

This room had previously discouraged any desire to take a bath. 

"I've decided to leave the hallway alone," Lily continued. "I don't know a spell to patch up the holes in the wall... You'll probably have to get some Muggle plaster from a shop nearby and I'll do what I can with it... Then I'll go to your room." 

Severus braced himself. This was the touchy subject he'd been expecting. Lily had told him she'd try to transform his prison-style bed into something fit for a prince. But the thought of her in his room - a dreadful place - made him uneasy.

"Your bed is fit for the dump," Lily said plainly. "I can't make it bigger, the iron's eaten away by rust... and the mattress is beyond repair." 

"I'll sleep in the sitting room," Severus declared with finality. "The sofa is perfectly comfortable." 

"Absolutely not!" Lily exclaimed, scandalised. "My bed is big enough for two." 

Severus objected, saying it was inappropriate and that the arrangement was only meant to be temporary. 

"This is your house and I'm the guest. There's no way I'm going to let you sleep on the sofa - and I don't want to be separated from Harry at night. I told you, you don't bother me. Besides, you don't even snore! "

Severus let out a soft chuckle. It was strangely satisfying to learn that he wasn't a noisy sleeper. 

"And..." Lily went on, a little embarrassed, "it makes me feel safer to have you there... Keeps the nightmares away. Helps me not to think about the worst." 

"You know," he said dryly, "if a Death Eater showed up here, they'd come through the living room first..." 

Lily gave him a playful pat on the shoulder. 

"I'm carrying a baby, thank you very much - don't hit me. I get special immunity for that... Kidding. No Death Eater would ever think of looking for me here, because nobody knows I'm in Cokeworth. Reassured?" 

Lily nodded with a smile, just as Harry decided not to hide any longer. 

"In that case," she said, "you'll be sleeping with me, as there's no need for you to stand guard on the sofa."

Severus had walked right into his own trap. He did enjoy sleeping next to Lily - he couldn't deny it. But they were no longer two thirteen-year-olds innocently sharing a tent. They were adults now, and Severus had feelings for Lily that were not reciprocated. She would never fall for him - skinny, sallow-faced, greasy-haired. She had chosen James Potter, the most popular boy in school - the one who had tormented him for years. How could Lily have fallen in love with someone she had once despised? 

"Lily, we've already discussed this..." Severus replied, less sure of himself now. 

He knew he was going to lose this battle - and to be honest, he didn't want to win it. Reason told him to resist, but another part of him was tired of resisting. 

"If you don't sleep in a proper bed, you'll be in a bad mood with your students... and then they won't learn anything." 

It was a solid argument. He finally gave in.

*

After dinner, Severus reviewed some of his lessons for the following day. He could have saved himself the trouble by using one of the standard exercises from the textbook, but that wasn't the kind of teacher he was. He wasn't entirely sure he was cut out for the job - he had no patience - but Severus Snape had no lack of discipline. He was every inch a scholar, a researcher, and such minds never abandon their scruples. 

Lily, having settled Harry upstairs, returned and leaned over his shoulder. 

"I envy you," she said quietly. 

Severus looked up at her. Her long red hair fell like a fiery waterfall over an old black jumper she'd pulled over her nightgown. 

"The job is yours if you want it," he replied dryly. 

"No... That wouldn't be wise. I can't teach at Hogwarts. There's probably a bounty on my head from Voldemort."

Severus winced at the name his former master had chosen for himself. Would there be a day when it didn't chill him? 

"I don't want to endanger children... innocent lives. It wouldn't be worth it. And you're very talented, you know. Much more than you realise." 

"You wanted to teach?" he asked. 

"If it hadn't been for this war, I would have done things very differently," Lily confessed. "I used to dream of becoming a pharmacist. But if someone had offered me a job at Hogwarts, I'd have jumped at the chance." 

The war had twisted so many destinies. Severus knew that better than anyone, the one who had made the worst choices. 

"Do you regret it?" 

"Joining the Order? Marrying outrageously young? Getting pregnant like a fool? Becoming a target and taking my whole family with me?"

Lily's voice rose and her eyes filled with tears. 

"No," she said, pulling herself together. "I joined because I had to. Foolishly, when I was eleven, I thought the wizarding world would welcome me with open arms, that all my wildest dreams would come true. But reality - and hatred - caught up with me. If I'd gone on with my life after school as if nothing had happened, who would have fought for my rights? For Muggle-borns like me? I'd have been a target anyway, just because of where I came from." 

She paused. Her hand, pale as milk, stroked Severus' cheek. 

"It's crazy, isn't it, how war speeds everything up. I feel like I've lived through decades and it's only been three years since I left Hogwarts."

Severus understood the feeling. On the other side, he had seen and heard things he wished he had never seen.

"I became a fighter, part of the Resistance... I married, I had a son... I've lost count of how many comrades I've buried. My address book is practically a cemetery. I was close to death myself, more than once. And I became a widow. We seem to have won the war, but at what cost?"

"How can you look at me without feeling anger?" asked Severus, troubled. "I was part of it all, one way or another."

"I haven't forgiven you for everything, Sev... Far from it. But you happen to be one of the last pillars of stability left in my world."

"Me? Stable?" Severus snorted.

"It's a figure of speech... You were my first point of reference in this world, and more importantly, my best friend. I know I can trust you. You won't fall back into this."

Lily then sat down on Severus' knobby knees and planted a kiss on his forehead.

"Will you show me what you're working on?" she asked with a smile.

Nervously, Severus pointed to a piece of parchment on which he had written the method for brewing Confusing Draught.

"Remember when Fina Blythe drank a ladle straight from her cauldron?" Lily said, scanning his notes. "She really didn't need any help being confused."

"How could I forget," Severus replied with a grin. "The girl was completely unmanageable."

"You have no idea," Lily laughed.

It was her third year. Horace Slughorn had set his students the task of brewing Confusing Draught, a potion that could be a formidable weapon if used to make an opponent act irrationally. Fina Blythe, a Gryffindor known for her reckless ways, had flouted one of the golden rules of Potions: never taste what you brew. She had wagered a galleon with Sirius Black that she could drink her own potion without ending up in hospital. It was a risky bet, considering her brewing skills were on a par with a troll's.

"She could've poisoned herself, but for once her potion worked," Lily continued.

"And Slughorn didn't even give her detention," Severus said bitterly.

"I think he was too amused by the whole thing... She even did an impromptu tap dance on his desk... And to be honest, her potion was excellent. Almost as good as ours."

Fina Blythe had brought a lot of laughter to the class, and she had other redeeming qualities. She had never been cruel to Severus, choosing instead to ignore him completely. And she had kept James Potter occupied by going out with him in her sixth year. Though he and Lily were no longer on speaking terms, Severus had appreciated seeing his worst enemy distracted by someone else. He never found out who had ended things between them.

"Quite a daredevil, if you ask me," Severus added.

"You didn't have to share a dorm with her," Lily replied teasingly.

"I can only imagine how lively your nights must have been."

"That's an understatement... In sixth year, I heard every detail of her relationship with James, whether I wanted to or not," Lily said with a grimace.

Had Lily liked Potter then? As they grew older, Severus had the impression that his best friend had become less and less indifferent to James. Perhaps that was what had hurt him the most.

"I wasn't in love with him then. I didn't care that James was a good kisser... or that he knew the location of every broom cupboard in the castle."

Severus stifled a laugh. Potter and his gang had probably explored every hidden passage Hogwarts had to offer.

"She eventually left him," Lily continued. "Passion took off like a Nimbus 1500... or rather, came crashing down like a misfired Comet 260."

"Lovely imagery," Severus said sarcastically.

"Not mine - Fina's. She played on the Quidditch team. You can imagine the metaphors I had to endure for months."

"Right... I'll keep an eye on my little Pickles' cauldrons."

Lily chuckled at the nickname Severus had given his students.

"How... How did you fall for Potter?" Severus asked hesitantly.

The amusement faded from Lily's face. It was a question that had gnawed at him for years. Why had she chosen James?

"It wasn't planned," Lily said defensively. "As you know, I became Head Girl in our seventh year and James was made Head Boy. I remember being furious when I saw him in the prefects' cart. I even considered resigning on the spot. But I didn't, because I believed I deserved the badge."

Severus nodded. Lily had always been a hardworking, responsible student. The same couldn't be said for Potter.

"As Heads, we spent a lot more time together than before... And I have a confession to make... We kept a bit of an eye on you that year. James was worried - and rightly so - that some of the Slytherins, who didn't bother to hide their ambitions to become Death Eaters, were recruiting among the younger students. "

This revelation didn't surprise Severus. He had always felt that Potter lurked nearby, a shadow on his periphery.

"We shared our concerns with Professors McGonagall and Dumbledore. Some students have been directed away... others, unfortunately..."

Severus lowered his eyes. He was no longer an impressionable novice - but he hadn't made up his mind yet.

"You were suspected, of course... But neither James nor I ever found solid proof. You rarely spent time with your fellow Slytherins, and I often saw you alone in the library."

"Those conversations didn't exactly take place in the common room," Severus replied, annoyed.

"No... I suppose you were more discreet than that."

It was rather insulting to the intelligence of some Slytherins to think they'd recruit new Death Eaters in plain sight.

"Still, we once caught Rosier and Mulciber chatting with some young Ravenclaws in the girls' bathroom on the second floor."

"Fair enough," Severus murmured.

"Our duties have brought us closer... But what really changed my mind about him was my mother's illness. When I found out she had cancer in October 1977, my whole world almost collapsed."

Lily's voice trembled slightly. Revisiting those memories clearly hurt her. Severus regretted not being there for her.

"So I threw myself into my work and overcommitted myself to my role as Head Girl. James noticed that something was wrong, that I wasn't myself... I was distancing myself from my friends and I could fly off the handle at a moment's notice. One day he told me to get it all out - and I did. From then on he was there for me. He became a kind of... confidant. "

Severus thought that if he hadn't messed things up so badly at the end of fifth year, he might have been the one to support Lily.

"Little by little, I began to appreciate him... and then to love him. In February 1978 we were officially a couple. You know the rest..."

Severus had witnessed their romance, and for years he had thought of a thousand reasons why Lily had fallen for Potter. Now he finally had an answer: Potter was there when Lily needed a friend the most.

"He understood what I was going through... I don't know if I ever told you, but James' parents were quite old when he was born. His mother, Euphemia, had always been in frail health. He grew up thinking he might lose her at any moment. They doted on him as a result, and in the end Dragon Pox took them both a few months after we were married. "

So Potter had his own problems at home - but they were very different from Severus'.

"You know," Lily added with a gentle smile. "I'm sure I'll be able to forgive you one day. It'll take time, but I know I'll get there. In the meantime, let's go to bed. A good teacher needs to be well rested. "

In bed, Lily curled up against his shoulder once more, and Severus fell asleep with ease - his last thought being that he would do everything in his power to earn the forgiveness of the woman he loved so dearly.