A week later, Crowley saunters into the book store to find Aziraphale leaning on his counter, staring at a brown box with utter befuddlement.

"Morning Angel," he says. "How do you feel about a late breakfast?"

"Hm? Oh, yes...maybe not just now."

Crowley frowns, eyes flitting down to the box, and leans on the opposite side of the counter.

"What's got you so bothered?" he asks. "Normally the B-word has you halfway out the door by now."

Aziraphale shakes his head and gestures to the box.

"Sorry, sorry, I'm just – this arrived this morning on a truck. Apparently I ordered it, but for the life of me I can't remember what it is."

"Huh, that is odd," Crowley says, leaning in and giving it a sniff. "Doesn't smell edible, pretty sure that's paper. Sure you didn't order something tempting off the net?"

The angel gives him a mocking flare. "I don't order from 'the net,'" he replies. "And I haven't been to any auctions or book stores recently."

He takes another look at the packaging, a finger tracing the logo on the side. It looks a little like a cartoon lion sitting on a clam.

"Hamaguri Publishing? Not one I know."

Crowley suddenly starts chuckling, and Aziraphale tenses.

"Crowley? What did you do?"

"Me?" Crowley laughs. "Absolutely nothing. I just happen to know that Hamaguri sounds quite Japanese."

It only takes Aziraphale a few seconds to register the importance, and his eyes close in a wince. The demon keeps chuckling.

"What about those brats? Haven't seen them around recently."

Aziraphale stands, leaning back from the box.

"No. They haven't been around for a few days," he admits. "I had Gokudera appear one afternoon, and then the lot of them arrived just before I closed, asked a bunch of random questions and disappeared. I'd rather hoped they'd given up."

"Not a chance," Crowley insists, leaning back himself. "This must be their next move. Want to do the honours?"

He reaches for a letter opener sitting in a pot by the side of the register, but Aziraphale beats him to it, clutching the small replica of a certain flaming sword in his hand, and quickly slicing it through the tape. When the top is opened, his eyes widen in horror.

"Oh, no..."

Crowley bursts into laughter again as Aziraphale gingerly moves the packaging out of the way and lifts up the first book, identical to the dozen others inside. The cover is a bright red, and has a little cartoon of a baby in a suit and fedora in the corner. He can only grimace at the title, declared in big white letters:

Negotiation for Dames.

"What in heaven's name is this?" Aziraphale says. "One of those 'basic life skills for Dummies' books?"

Crowley grins and lifts one out, flicking through the pages in amusement.

"Some kind of knock off by the looks of things. You know, I thought about taking credit for those."

Aziraphale winces. "I did too. Rather glad I didn't to be honest."

Crowley grins and tosses the book back inside the box. "Same here. Risky ground, all things considered."

"But why on earth would they be sending me a box of self help books?" Aziraphale asks, just as the door opens to reveal the instigators in question.

"Oh good, they arrived to the Extreme!" Ryohei announces, walking in with a smile matched on each face – except that of Tsuna, who looks a little sheepish. Aziraphale gives a tight smile.

"Good day," he greets. "I had rather hoped you'd left."

"You know we can't, Mr Fell," Tsuna replies. "Not without a book."

Aziraphale glances down at the box again and raises his eyebrows.

"I'm relatively certain that you said you had to buy a book," he says. "I don't think giving me one counts."

Before he can answer, Gokudera has slid in front of his 'boss,' with a grin that wouldn't look out of place on his favourite Demon's face. "Give? Who said anything about give? You bought those books for stock. We've got the order form and everything."

Aziraphale blinks. "I...beg your pardon?"

The silver haired teen produces a printout with a cackle. "Here, see? Last week, Mr. Fell and Co ordered a dozen of the very first book Hamaguri Publishing produced. As a special promotion for our first customer, you didn't even have to pay anything."

Crowley immediately grabs the sheet, glancing over before grinning, and handing it to Aziraphale.

"Got to admit, that looks like your phone number," he says. "Some one from this building made a phone order."

The angel swipes the paper, and thinks back to the last time he'd seen the group. They had been hell bent on catching his attention, but since they hadn't been trying to steal books, he'd not paid that much care...and the black haired one had been out of sight when he'd tried to wrest a title from Gokudera.

"See, last week, I was taking to Mr Crowley," Tsuna begins, ignoring the way the shopkeeper immediately turned to glare at other man. "And he made me realise you love your collection. And how unique and special it is. You'd never sully it with something that wasn't truly special, so if you ended up with something cheap and tacky, you'd be happy to get rid of it."

"Oh I don't know about that," Aziraphale mutters, still glaring at Crowley, who is finding a patch of wall very interesting right now.

"Originally I thought we could just give you a book to sell us," Tsuna explains. "Like one of those airport paperbacks, but then I realised it wouldn't count. We had to make sure you ordered the book officially."

"Sorry for the delay, but it took a while to make the logo, and then make the stock, to the Extreme," Ryohei offers.

"You set up an entire publishing company, just to get these in the door?" Aziraphale asks. "Isn't that rather, 'Extreme?'"

"Please, it's the Internet Era," Gokudera counters. "Took five minutes to set up a website and register a web company. God bless online Capitalism."

"Oh I assure you, she had nothing to do with it," Crowley snickers, and Aziraphale rubs a hand over his face.

"You really thought I'd put these in my shop? They're hardly my usual stock."

"Oh, but they are," Gokudera replies. "We made sure of that. Check your records."

Aziraphale frowns, but opens the drawer he'd been hiding the stock take checklists away. He only has to lift a few pages to find the addition, happily inserted between his cherished titles.

"Thanks for doing your stock take while we were here by the way," Yamamoto offers with a smile. "Would have been hard to get access to your stock list otherwise."

If Crowley has to hold in his laughter any more, his body might actually combust. Aziraphale gives him a pointed look and jerks towards the back room with his head. The demon has genuine trouble making it there, but manages to hold in his cackles until after he closes the door. When he's gone, the angel shakes his head and stares at Tsuna.

"Why in heaven's name would you send me so many?" he asks, and Tsuna gives a sheepish smile.

"Because we had to do it right," he explains. "We needed to set up an official company, and set up an official order from this store, and make sure they were on your stock list, otherwise we couldn't say the book was purchased here. And if we only sent you the one book, you might just throw it away on principle, or keep it on the grounds that it was 'one of a kind.' An entire package, you'd probably try to send back, and that gave us time to get here."

Yamamoto raises a hand. "Plus, printing to order is really expensive and the only place we found willing to do a rush job insisted on 12 minimum."

Despite himself, Aziraphale feels a smile starting to crawl onto his face, and the group step closer with hopeful grins, as their boss plucks one out from the cardboard.

"Well?" Tsuna asks, holding up the ludicrous item. "Would you be willing to sell us a copy of Negotiation for Dames? I'm happy to pay any price."

Aziraphale gives in, and lets himself give a genuine chuckle.

"You, could be quite terrifying in a few years, Mr. Sawada," he says. "Well done indeed."

Tsuna goes slightly red at the compliment, and Aziraphale walks over to his register.

"Now," he says. "Exactly how does this thing work again..."

The shopkeeper finishes signing the hand written receipt with a flourish of ink, and happily hands it over.

"There we are," he says. "Enjoy your hideous self-improvement book. I hope you don't mind if I burn the rest of the copies?"

"Aww," Yamamoto whines. "But we worked really hard on them."

"I drew all the illustrations to the Extreme!" Ryohei insists.

"Guys, he legally owns them, he can do what he wants," Tsuna tells them, looking over his shoulder. "And lets be honest, they're not actually all that good."
'Most of it what lifted from other books on the subject,' he thinks to himself. 'And all the additions Gokudera included are too complicated for anyone to follow. He'd probably be doing the world a favour by burning them.'

Aziraphale might be reading his mind, because he's glancing back into the box with a look of distaste.

"Perhaps I'll keep them after all," he muses. "I can hand them out to any other little would-be heirs and save myself some trouble."

Gokudera's eyes light up.

"Second printing? We could turn some profit and help you ou-"

"No!" Tsuna yelps, swinging round and cutting off his right hand before he runs down that rabbit hole. "There will be no more printings! Besides."

He holds up the book and smiles.

"If he does, it could cheapen our achievement. Congratulations guys, we did it!"

The three teens grin.

"Mission accomplished!" Yamamoto says, while Ryohei gives him a thumbs up. Gokudera happily walks over to grab the book himself.

"I can't wait to show the bronco this," he says. "Who says you can't get a book from the Devil of Soho?"

Aziraphale makes a strangled sound, lunging over the counter in shock and letting the box collapse to the floor.

"The what of Soho?"

Before Tsuna can answer, there's frantic footsteps coming from the back room, and Crowley all but lunges into the door way, arms braced on the door frame. Behind the glasses, Tsuna's pretty sure his eyes are all but bugging out of their sockets, wearing a grin that goes from ear to ear.

"The what of where?"

Everyone glances at each other, before all turning to Tsuna, who winces.

"Oh, um, I guess you didn't know?" he says. "That's kind of what people who try and get books from you call you. Because your shop is on a crossroads? And you'd rather sell your soul than a book, and, um..."

Tsuna bites his lip, because it sounds so embarrassing to explain this to the person in question. Especially since Aziraphale looks like Tsuna just told him he'd murdered his whole family and drowned his puppy for good measure. His mouth keeps moving reminiscent of a goldfish, unable to speak, but everyone's attention quickly leaves him, when they start hearing a high pitched sound from the inner doorway.

Crowley has burst into laughter – hysteric to the point that his legs give out and he ends up on the ground, slamming a fist into the floor as he tries to contain his glee.

It's enough to help the book seller recover, because he swings to face the cackling man

"Crowley! Do not tell me this is your doing?"

"Oh heaven's no, Angel!" Crowley manages to splutter out, rolling onto his back and wrapping his arms around his torso, legs flailing. "This is so much better than anything I could ever do!"

Tsuna glances at his friends, who are all wearing grins at the man's reaction. He doubts he's much better – he'd forgotten the man's pet name for his partner. The man in question just sags on the counter, hand rubbing his temple.

"There will be no living with him after this," he mutters, though Tsuna can definitely see the smile he's desperately trying to smile.

When Crowley recovers, he pulls his legs under him and leans back on one hand, while the other sets his glasses back in place.

"This might just be the best day of my life," he announces, still wearing a mad grin. "Such a naughty Angel, Aziraphale."

He doesn't even bother to glance in the man's direction, merely pointing a finger in the back room's direction.

"You will be dropping this, my dear. I assure you."

From the way Crowley's grinning, Tsuna highly doubts it. But as he glances for the door, and spots Gokudera still looking wantonly at the shelves, he finds his mouth opening almost against his will.

"Can I ask why you refuse to sell?" he asks as he turns back. Mr. Fell almost looks surprised at the question. "I mean, if you don't want to sell, why even have a shop in the first place?"

Mr. Fell smiles, and glances round the room.

"I simply needed a place to store them," he explains, and Tsuna's jaw drops.

"But...why not just have a private collection!" he exclaims, and Mr. Fell frowns.

"Greed is a sin!" he insists. "I couldn't hoard all this away forever. With a shop, people are welcome to read."

"What?" Gokudera yelps in horror. "That's just false advertising! Why not just open up a coffee shop with a library or something?"

Aziraphale shrugs. "I like the shop?"

Gokudera growls low in his throat, and when Tsuna sees him start to reach into his jacket, he silently gestures to Yamamoto, who happily sweeps in.

"Okay, time to go," Yamamoto offers, grabbing Gokudera by the shoulders and steering him by the shoulders. "Let's vent your frustrations elsewhere, buddy."

"But-him, the, so much...die..."

"I know, I know, big, deep breaths, Gokudera."

"You can scream outside, to the Extreme!" Ryohei offers, quickly following the two, and Tsuna falls in line, glancing back at two of the stranger people he's met in recent years.

...And that's actually saying something at this point.

"Thank you for the book," he says. "And please don't take this the wrong way, but I really hope we never meet again."

Crowley grins and gives a mock salute, while Aziraphale gives an amused wave, and Tsuna happily lets himself out the door.

"So, should we fly home tonight, or celebrate in London?" he asks his Guardians as they walk down the street. He knows for a fact that Gokudera hasn't made it to any of his ghost tours.

"Celebrate to the Extreme!" Ryohei insists, and Yamamoto laughs.

"Yeah, now that we've got the book, we can finally relax."

Gokudera however, forces himself out of his mumbling to glance back at the building.

"I don't know," he says. "I mean, we accomplished our goal, but Tenth, we still don't know about their connection to...you know, that guy."

Gokudera shudders and glances around, as if merely talking about Kawahira could summon him, and they all frown.

"W-well, we don't actually know that they're connected," Tsuna offers. "Just that they know about the stones."

"And that they're extremely old," Ryohei adds.

"I'd rather not tempt fate," Gokudera says. "Last time I was alone with Mr. Fell, he did something that made it impossible to lie. I couldn't even stop talking. If they decide to chase us, we might end up breaking omerta."

Tsuna frowns. "Actually...when I met Crowley, it was really hard not spill everything I knew about Vongola. He said something, and I just wanted to start talking and never stop."

The trio pause on the street.

"Really?" Yamamoto asks. "That's not like you."

Tsuna nods. "I don't know. To be honest, it almost felt like he was...tempting me into doing it."

Gokudera pales. "You know, they say demons can tempt people into almost anything...and angels seek truths..."

The teens stand motionless, glancing at each other.

"It can't be," Tsuna says. "You don't think that nickname's actually literal..."

Everyone's eyes glances between each other, before they burst into laughter.

"No way, to the Extreme!" Ryohei laughs.

"Yeah, even our lives aren't that crazy. We have enough self-proclaimed demons running around without thinking we've met an actual angel and demon," Yamamoto says.

"I know none of you are all that religious, but I am way too Catholic to be having this conversation," Gokudera begs, still looking a little pale. "Can we please go before my brain gets locked on this topic?"

Tsuna winces, and pats his right hand on the back.

"Oh, sorry Gokudera," he says. "We're just being stupid. Let's just get back to the hotel, and we can forget all about this."

"Sounds good to me," Yamamoto agrees.

"Extremely good idea!"

From a corner window, Crowley releases his miracle to hear their words, and lets the blinds fall back into place.

"Huh, I really thought they'd figured it out."

At his side, Aziraphale smiles.

"Well, it's probably for the best my dear. Probably wouldn't be too wise to have members of the criminal underground knowing our little secret."

"Still a pity though," Crowley says. "Not often you meet a Mafioso that didn't spot the signs."

"Yes, but most of them were clearly raised in Japan, not Italy," Aziraphale offers. "Christianity never quite managed to get a leg up there."

Crowley smirks. "Right. Give Tsunayoshi a few years of Italian indoctrination, and one day he'll wake up in the dead of night in horrified realisation."

Aziraphale nods. "Poor boy. I hope it doesn't affect him too badly. How on earth does someone like that end up in a position like his?"

"Some people are just born under unlucky stars, Angel," Crowley says. "Though I'd feel more worried for the criminal underground. It's due for a shake up if that's the next generation running round."

Aziraphale smiles, and then hesitates as he remembers something else they'd eavesdropped.

"But what was that about stones?"

Crowley leans away from the window, and starts heading towards the back room again.

"Oh, didn't you notice? They were all wearing shards of holy rock on their fingers."

The angel stills, before quickly chasing after the demon.

"Truly? I didn't sense anything."

"Neither did I at first," Crowley explains. "Didn't even realise what I was looking at still it was practically under my nose. It was hidden under all that criminal sigil pomp and circumstance, but it was a holy relic alright."

He happily falls into a seat as Aziraphale enters the room, and the angel looks puzzled, grabbing one of his own.

"But, how in heaven could something like that fall into the hands of mortals?" he asks. "I mean, the only time anything like that ever happened was...oh dear."

"Angel?"

The shopkeeper has gone quite pale.

"Do you remember an Angel that often took blessings in Japan?" Aziraphale asks. "Became quite fond of food before he fell? We used to meet every now and then for a meal, he knew the best ramen restaurants."

"Wait, wait, I remember now, yeah," Crowley says. "He got really into the Tale of Genji and changed his name, Kawakara or something, right? But he didn't fall."

"I think it was Kawahira, my dear," Aziraphale corrects. "And you're wrong, I'm sure he fell."

Crowley frowns and leans up from his seat.

"Uh, no he didn't. Last time I saw him was a few centuries ago on Earth, and he was still clean as a whistle. I'd have noticed that kind of hygiene in hell's briefing room."

Aziraphale pauses.

"But...well...he can't still be an angel," he insists. "There was the whole incident."

"What incident?" Crowley repeats, and Aziraphale waves a hand.

"Oh it was quite the scandal," he says. "He and another Angel, Sepira, I think, were given the duty of protecting some rather valuable heavenly artefacts, and did a rather poor job of it I must say."

Crowley grins and raises his glass.

"Glass houses Angel. I seem to remember a flaming sword that went missing for a few thousand years."

"Yes, well," Aziraphale huffs. "At least I didn't break items filled with holy power into seven pieces and nearly start a heavenly war with human soldiers."

That has Crowley interested, feet hopping off a table and planting on the floor as he leans over.

"What?" he gapes. "I didn't hear anything about this."

"It was in Italy my dear," Aziraphale explains, and Crowley winces, nodding in understanding. Italy has always been a sore spot for demons; with so much consecrated ground they basically spend any time there playing hopscotch. And to be honest, once the Mafia really got up and running, it did a pretty good job balancing out the Catholic Church, and neither Heaven or Hell saw much point in bothering with the country.

Although granted, these days it was hard to tell which organisation was on what side, not that Aziraphale or Crowley were going to poke that dilemma too closely.

"To be honest, I only really heard about it after the fact myself," the Angel continues. "The relics were literally built into the foundations of the planet. Their destruction could have set off Armageddon early. But Gabriel insisted they'd found a compromise and everything was settled. I never saw either of them in heaven again so...I assumed they'd fallen."

Crowley shook his head.

"Trust me Angel," he says. "If Hell had gotten wind of that, no amount of consecrated ground would have kept old 'Lucy and the rest of his lot away. They're not in Hell."

Aziraphale frowns.

"...Perhaps I should be more concerned about this," he says, only for Crowley to wave it off.

"I wouldn't worry about it Angel," he insists. "Those rings had at least a couple of centuries on em. If nobody's noticed yet, I doubt it's your problem. Though maybe I should risk the consecrated ground and check out Italy in a few years. Something tells me that group is going to be hilarious when they inherit. Might even get another commendation out of their antics."

The angel rolls his eyes.

"I thought you were holding off on taking credit after the Tumblr incident?"

"Oh come on Angel," Crowley says with a grin. "Holy powers, Mafioso, Italy, and an honest man in power. How could anyone pass that up?"

Despite himself, Aziraphale smiles.

"Well, it has been a long time since I had good gelato," he admits. "Perhaps we could just pop in for an update in say...ten years? Unless they burn something to the ground before then, anyway."

Crowley grins.

"It's a date, Angel."

END

...And done! Thank you for letting me play in two universes that probably shouldn't have gone together, but gave me a lot of fun doing so!