The conversation with Sirius happened the next morning.
He found Sirius in the guest room corridor after breakfast - Sirius had already eaten, was in his travelling robes with the specific energy of someone who was going somewhere and was not in a hurry about it.
They sat on the window seat at the end of the corridor, which had a view of the grounds, the April morning doing what April mornings did in Scotland, which was be uncertain and occasionally beautiful.
Ron laid it out in the order he had planned: the bookshop first.
Sirius listened with the quality he had when something was engaging him fully - leaning forward slightly, the grey eyes clear and attentive, the habitual restlessness settled into stillness.
'Lupin's business,' Sirius said, when Ron finished the first part. Not a question. A statement of recognition - he had already understood, from the shape of it, that the bookshop was for Remus in a way the vehicle club was not.
'Diagon Alley,' Ron said. 'Near the Leaky Cauldron end, where it quiets down. Good bones, the right size for a proper shop with a café section. Lupin's already built a proposed catalogue - four hundred titles, organized by subject and cultural significance.'
Sirius laughed, short and genuine. 'He told me about the catalogue. He described it as preliminary.'
'The Lupin version of preliminary is what most people call thorough,' Ron said.
'Yes,' Sirius agreed. He was quiet for a moment, looking at the grounds. 'The café. That's the part that makes it legitimate for him - not just the books. Somewhere to sit, read, talk. Somewhere that has the quality of a room you'd want to be in for its own sake.'
'That's the design,' Ron said. 'Nothing that draws attention. Nothing that requires explanation. Just genuinely good books and a good cup of tea.'
Sirius nodded slowly. Then: 'The second part.'
Ron told him about the vehicle club.
The shift in Sirius's expression was immediate --- not performed interest but actual interest, the specific quality of someone who had been presented with a problem their particular abilities were suited to and had already begun working it in their head.
'Muggle vehicles, magically modified,' Sirius said. 'Private club. Invitation only.'
'Workshop and a private track,' Ron said. 'Outside the alley --- you'd need space for the full mechanical work and for actual riding and racing. Members who meet the entry criteria. Rigid on vetting. No one who can't be trusted to keep it private.'
'The mechanical work,' Sirius said, with the quality of someone confirming something against an internal model. 'That's the real part of it. Not the exclusivity --- the work itself. The problem of making a Muggle machine do things it wasn't built to do, and doing it so well that it becomes something else entirely.' He paused. 'I did it to my own bike. I've been thinking about it for twenty years.'
'I know,' Ron said.
Sirius looked at him. 'How do you know that?'
'The way you talk about the bike,' Ron said. 'And because it's obvious. It's the thing you're actually good at that no one gave you space to develop. The magic-and-mechanics intersection is a narrow field and you're one of the few people who understands both sides of it from the inside.'
Sirius was quiet for a moment with the expression he had when something landed correctly.
'The membership,' he said. 'You said invitation only. What's the entry condition?'
'Someone who can be vouched for by two existing members,' Ron said. 'And a conversation with you first, in person. Not a formal interview --- you'd know within ten minutes. You've spent twelve years reading people in Azkaban. You're very good at it.'
Sirius looked at him with something that was half amusement and half something more complicated. 'That's a diplomatic way of describing what Azkaban does to a person's instincts.'
'It's an accurate way,' Ron said. 'The instinct is real. You should use it.'
A pause. The April light moved across the grounds --- a shaft of it, briefly, through the uncertain sky, touching the grass.
'The two businesses,' Sirius said. 'What's the structural relationship between them?'
'Separate,' Ron said. 'Different locations, different staff, different registration. The only link is the ownership, which is private. The bookshop-café is Lupin's in all practical senses. The vehicle club is yours. Neither needs to know what the other is doing on any given day.'
'And the intelligence function.'
'Isn't a function,' Ron said. 'It's a consequence. The right people, in private spaces, over time, building trust. You don't design it. You don't name it. You don't keep records. If something important surfaces through those conversations, you use it the way a person uses something they heard while sitting in a room --- carefully, with judgment, without attribution.'
Sirius was quiet for a long time. He had the quality he sometimes had --- the thinking quality, the one that had been visible since July, the mind that had survived Azkaban by keeping itself working on problems in the dark.
'The name,' Sirius said finally. 'For the bookshop. It needs something.'
'You need something for both of them,' Ron said. 'The bookshop should carry the Marauder connection quietly --- the four emblems. Stag, dog, wolf, and instead of the rat a lily for Harry's mother. A name that carries the quality of the Marauders without the word itself.' He paused. 'The vehicle club is different. That's yours alone. Name it what it is.'
Sirius was very still.
'The Four Emblems,' he said. Slowly. As though testing the weight of it. 'For the bookshop.'
'Yes,' Ron said.
A silence.
'And the vehicle club,' Sirius said. 'You said name it what it is.'
'It's a workshop,' Ron said. 'For people who work with their hands and understand that modifying a machine is a form of argument with the limits of what's possible. Call it something that says that.' He paused. 'Black's, maybe. Simple.'
Sirius looked at him with an expression that was complicated and clear at the same time.
'And I would like a fifth emblem,' Ron said. 'On the door of the bookshop. The Witness mark. The eye in the circle. One only visible to the owners'
Sirius looked at him.
'The Witness,' Sirius said. 'Remus told me. The postcards. The leaving feast photograph.' He paused. 'That was you.'
'Yes,' Ron said.
'Harry didn't tell me,' Sirius said.
'Harry knew,' Ron said. 'He understood why it needed to be kept.'
Sirius was quiet for a moment, looking at the grounds. 'The eye ,' he said. 'Not the stag, the dog, the wolf, or the lily. A different emblem. Your own.'
'Yes,' Ron said.
Sirius looked at him for a long moment with the grey eyes that missed very little. 'What are you investing?'
'Fifty thousand,' Ron said. 'For the bookshop. Harry will want in as well --- the same amount.'
'He already said so,' Sirius said. 'He wants his name on something real that he built with people he trusted.' A pause. 'I'm putting in two hundred thousand. Split between the two businesses as the costs require --- the vehicle club will need more space, the bookshop less.'
Ron did the arithmetic: three hundred thousand total. Enough to do it properly. Enough to do it without compromise.
'The security,' Ron said. 'The bookshop building. If there are existing wards on the upstairs space ---'
'There are,' Sirius said. 'I found a building. Near the Leaky end, been empty three years, Goblin holding company owns it outright. The wards on the upstairs are Ministry-grade and then some. Black family work, from the architectural style. Someone put real magic into those walls.' He paused. 'I've been to see it twice.'
'Good bones,' Ron said.
'Very good bones,' Sirius said. He looked at the grounds for a moment in the way he looked at things he had made decisions about. Then he turned back. 'The Four Emblems,' he said. 'And Black's.' He paused. 'Yes. That's both of them.'