Draco ran his knuckles gently along the barn owl's back, whispering soothingly in a pre-emptive apology for what it was about to endure. It was no mistake he'd chosen a sleek barn owl for the mission. Of the owls at his disposal, the barn owl was the only one likely to drown out Daphne's screeches with its own.

Fastening the carefully crafted message to its leg, Draco lifted the owl and saw it off at the window. Normally he would have sent a more personalised message with one of his own owls to cancel with a client-it was just decent business practice when breaking appointments. But Potter insisted it would be fine to use one of the Ministry's owls to expedite the job.

"And anyway," he'd said, "Ministry owls are used to dealing with irate recipients. They're equipped with better wards than most wizarding homes."

Draco was not about to underestimate any of the Greengrass women, but given his inability to be more than a few yards away from Potter, he agreed.

"I can reschedule my appointments for today," Draco said, turning back to Potter as the owl took flight, "but I cannot put them off indefinitely. I do have commitments to meet and a business to keep afloat."

Potter stared at him with something akin to bemusement. "Okay," he said. "We'll go see Hermione and check in on your shop after. Fair?"

Draco pursed his lips and adjusted his grey robes. "Fair is not quite the appropriate word, no," he said, "but it is acceptable."

"How gracious of you," Potter said and held out a hand. Draco almost took it without thinking, so natural did the action seem. But just before their hands touched, both of them withdrew. Draco eyed the ring on his hand warily. How much was the spell doing? He felt much more at ease with Potter than he had felt with anyone before, let alone his school rival.

Remembering that day on the Hogwarts Express all those years ago, Draco wondered how different things might have been if Potter had taken his hand, his friendship.

One look at this face and Draco was sure Potter was thinking along similar lines. He scraped a hand through his messy hair and exhaled as if to say 'sod it all.'

"I need to side-along you," he said, "to where Hermione is. We're going to end up having to touch. It doesn't necessarily mean anything." Then, in jest, he added, "I promise I won't bite."

"But I might." The words were out of Draco's mouth before he could even formulate them in his mind. His mouth snapped shut, and he swallowed hard against the dryness in his throat. Potter, however, maintained that insufferable look of amusement.

"I'm an old-fashioned bloke, Malfoy," he said, offering his hand once more. "At least buy me dinner first."

Draco rolled his eyes and slapped his hand down on Potter's with more force than was strictly necessary. He was aiming for painful, but the moment their skin touched a wave of pleasure rocked through him. Warmed from the inside, Draco tried not to look at Potter again but suspected he felt it too.

The familiar tug of Apparition took hold, spinning the world out from under Draco's feet and spiriting them away to wherever Granger made her home. Draco strongly suspected it was a large library of some sort.

And just like that, he'd fallen back into pace with his old rivalries. Potter had a knack for dredging up memories Draco tried very hard to keep buried.

When the world rematerialized around them, Draco found himself standing in a large, vaulted room with apparently no doors or windows. To Draco's knowledge, it might not even have had walls. He was surrounded by stacks upon stacks of books. The piles rose so high in every direction they obscured any light that did not come from directly above, and the only lighting seemed to be enchanted floating fairy lights that did little to dispel the shadows.

The fairy lights dimly illuminated some of the spines of the books to Draco's side. He glanced at the titles. 1001 Uses for Flobberworms, A Historical Account of Mathilda the Mad's Sub-Saharan Adventure, A Definitive Guide to Magical Inheritance Law, and Quick Quips and Other Rhetorical Devices: A Guide to Conversing with Muggles, were titles among the ones Draco could make out. He concluded from this that the books were stacked in no particular order.

"Where the hell are we, Potter?" Draco asked, denying the urge to pull out his wand.

"Storehouse five," Potter answered, as though that made any sense. He set off down the alley of books, leaving Draco to follow or be lost in the maze of tomes. "One of the many places the Ministry keeps all the things it accumulates. Some of it is donated for historical purposes. Most is confiscated goods from Dark Wizards and the like. Storehouse five is books, obviously."

Draco sniffed. "I suppose Granger saw this and felt compelled to impose order on the chaos?" he asked. Potter made a sound halfway between a snort and a grunt.

"Hermione isn't here to organize the books," Potter said as they came around a teetering tower of textbooks. "She doesn't work for the Ministry."

One eyebrow arched, Draco tilted his head. He would have bet money in school that Granger would end up working for the Ministry. In fact, of the Golden Trio, she seemed the most likely to lean toward government work.

Potter stopped in front of something that might have been a desk beneath all the scrolls of parchment piled atop it. It sat in what might have been the centre of the storehouse, but given the height of the walls of books, Draco couldn't be sure of anything.

"What does she do, then?" Draco asked, unconsciously stopping when he was only inches away from Potter. Potter seemed to sigh as Draco moved closer, but when he noticed, he cleared his throat. Draco stepped aside, putting more distance between them than he meant to, and he forced himself to study the wall of books again. "Surely someone of Granger's intellectual calibre would not find themselves in this dank dungeon unless they had good reason."

When Draco brought his attention back to Potter, it was to find the auror watching him with something akin to surprise on his face.

"I'm a historian," Granger said, appearing suddenly from behind the mound of scrolls and books. Draco started when he saw her, amazed that he had somehow missed her presence. She was huge. "And thanks. The Ministry is allowing me access to their collections in order to compile a newer, more accurate History of Magic textbook." Potter beamed at her, then quickly rushed over to help her with the tome she was carrying. It was a massive, leather-bound book with brass clamps and gold filigree across the cover that reminded Draco of some of the books he used to play professor with when he was young. He reached out to take it from her only to have her swat at his hand and drop it with a thump onto the desk, scattering scrolls as she did. "I'm pregnant, Harry, not an invalid."

And she was. By the sight of her she was ready to pop at any moment.

"Good afternoon, Granger," Draco said, trying to recover himself.

"Malfoy," she said. "And it's Weasley now." Draco said nothing to that. She wiped at her forehead with the back of her wrist and exhaled gruffly. With a wave of her wand, a light breeze wafted in around the three of them. "That's better. Now. I've collected all the books in Magical Binding Contracts and the various pureblood family histories I could find that might be useful." Catching Potter's incredulous look, she added, "oh, honestly, Harry, Neville sent me a Patronus the moment you got back to the Ministry."

"You did all this in two hours?" Draco said. Granger-because he couldn't bring himself to think of her as Weasley-brushed it off.

"Well, I would have been faster, but I'm not moving quite as quickly as I used to these days," she said with a vague gesture to her belly.

"Thanks, Hermione, you're brilliant," Potter said. "So what have you found?"

"Did I not just say?" she snapped suddenly. "I found you all these bloody books and that's not enough? You try navigating around all these stacks of books when you're the size of a bleeding Mountain Troll." Potter stepped back, his expression apologetic. Draco felt as though a rush of ice washed down his spine, and he suddenly felt very aware of how long it would take him to draw his wand. Granger's face was flush, but after a moment, she took a deep breath and dropped her head. "I'm sorry," she said, as though on the verge of tears. "It's the damn hormones. I'm a lunatic." She toddled backward and sank down into a chair, a hand to her forehead.

"Hermione, it's all right," Potter said, attempting to placate her. Draco thought Potter probably had a death wish, but that was nothing new. "I didn't mean anything by it."

Shrugging him off, Granger sat up straighter and turned her attention to the book she'd dropped on the desk. "Malfoy, you said the ring dated back to the fourteenth century, yeah?" Draco nodded, his eyes falling to the ring on his finger. He had to keep reminding himself it was there. It had already become so natural to have it on, he wondered if it would feel strange to remove it. "So we can eliminate all the pureblood families that don't trace their lineage back that far."

Granger flipped open the book, and as she did, Draco felt his breath catch in his chest. There were ink splatters and little drawings along the margins of some pages that Draco recognized all too well. The book was a collected family tree of all the pureblood families in the United Kingdom and it was called The Pure-Blood Directory.

"So what does that bring us to?" Potter asked as Granger drew one finger down the list of families.

"Still quite a few," she said, "The Blacks, the Crabbes, the Gaunts, or rather the Slytherins, the Notts, the Malfoys, the Potters, or Peverells, the Weasleys, and the Prewetts." As she drew her hand down the list, she paused slightly at Draco's family name. There were ink drawings around it, little crowns and snitches and bold, childish lettering that read best. Granger cocked her head to the side and looked up at Draco. Potter inevitably read the page and followed her gaze.

"My apologies about the ink," Draco said, schooling his face into an expressionless mask. "I was too young to know better than to deface a historical book of this kind."

"This is yours?" Potter asked, but the look on Granger's face suggested she already knew that. "Why does the Ministry have it?"

Draco plucked at an invisible thread on the sleeve of his robes and cast it aside. Trying for nonchalant, he said, "honestly Potter, don't you read the reports? Surrendering all potentially dark objects was part of the terms of my sentence."

Potter glanced at Granger. "But this is just a book of pureblood families," he said. "How is that dark?"

"I did not get a say in what the Ministry took and what they left behind," Draco said. "They confiscated anything and everything they deemed inappropriate to remain in my custody, which apparently meant all the antique furnishings, jewellery, and books that Malfoy Manor housed, regardless of their provenance." Potter looked as though he was about to say something, but Draco didn't want to hear it. "Shall we continue?"

Granger cast Potter a look before moving on. "We need to narrow this down further. Is there anything else you can tell me about the ring that might help?"

Grateful for the return to solid ground, Draco studied the ring on his finger more closely. "Binding spells this strong were more common in unions between families that didn't fully trust one another," Draco said, "although that, in itself, is not unusual given the time period. That does narrow down the poorer of the families, though. Only two very wealthy families would both with a bonding spell this strong, to protect their interests on either side."

"These bonding spells get more heart-warming by the second," Potter said.

"Who wrote this book?" Granger asked, studying the list. "It actually does include details on family earnings and net worth."

Draco rolled his eyes. "As I said, these things mattered once." They both cast Draco a scathing look, to which he replied, "they may not matter now, but long ago marriages were about family survival. Everything was political, and everything was about power. There were far more purebloods back then than there are now. Many families just died off entirely. A spell like this is how the wealthier families ensured their own survival."

"Well, that does narrow it down," Granger admitted. "The Crabbes and the Gaunts were almost insolvent at that time. The Notts were what you might call middle-class at best. The Weasleys and the Prewetts were in the range of comfortably wealthy, but the three wealthiest families on this list by far are the Blacks, the Malfoys, and the Peverells."

The pull in Draco's stomach, the one that drew him to Potter, grew stronger. He found himself standing next to Potter, their arms almost touching. Heat rose between them and curled on Draco's skin.

"Based on my diagnostics," Draco said, trying to ignore the pull, "the ritual bonding had to be unfulfilled in some way. Either it was never completed, or the bond was broken before consummation. It could even be that one family somehow managed to betray the other, breaking the rules of the spell. That way the bonding magic would seem to have dissipated but instead remain dormant."

"And you couldn't have mentioned that earlier?" Potter asked. Draco made a face and found Potter staring at him. He swallowed hard.

"I've only read about it in theory," he explained. "And it applies given our current circumstance, but there was no logical reason to assume it was the case before the bond took hold of us."

"And yet this whole mess would have been avoided." Potter leaned in closer in what he clearly meant to be an intimidating way. But to Draco it read as leering. "Seems a bit convenient you only remember it now."

Draco sneered, "are we back to thinking I orchestrated this whole thing? To what end? So that I might ruin my budding business? Or perhaps you thought I just enjoy submitting myself to Ministry searches and interrogations. You aurors do so love your well-trodden paths. Try some imagination for once, Potter. Find a new suspect."

"I dunno, Malfoy. Maybe you wanted to get some publicity fo-"

"Will you two shut up?" Granger snapped. Draco and Potter turned to her, and Draco was suddenly aware of how close he was to Potter. He could smell peppermint on Potter's breath, the light spice of his shampoo, and the subtle tang of sweat. Potter's pupils were dilated, so wide they nearly eclipsed the green. "I think I might have found something."

Turning his attention to Granger, Draco took deep, slow breaths, his mind racing. No one had ever managed to rile him like Potter. No one. At least he wasn't the only one shaken by their argument. Potter was clearly thrown as he leaned over to look at what Granger had found.

"It's hard to be certain," she said, eyeing them both warily, "but I might have found something that fits what you said. There was a couple marked to be married here, but their dates of death are off. The book lists a wedding day, but their dates of death are the same day. They died the day they were married."

A chord struck in Draco's mind, but he couldn't make out the source.

"That sounds like what we're looking for," Potter said. "Who were they?"

Granger paused and gave them both a significant look. By the time she said it, Draco remembered.

"Perseus Malfoy and Helena Peverell."