He told Lupin about Uganda toward the end of March, on a Thursday after the Patronus session when the others had gone and they were packing up the practice room.
Not because Lupin needed to know --- this was July, not term time --- but because there was something he had been wanting to ask Lupin for several weeks and the Uganda context was the right frame for it.
'I want to talk to you about something before the end of term,' he said.
Lupin looked at him with the attention he gave things he suspected were going to be more significant than they appeared.
'The end of term,' Ron said. 'You're leaving.'
Lupin was quiet for a moment. 'Yes,' he said.
'I've guessed since December,' Ron said. 'You have the quality of someone who is here for a specific purpose and is aware it has a duration.'
Lupin looked at him. 'That's perceptive.'
'It's observation,' Ron said. 'You've been a good teacher. I wanted to say that directly before the term ends, rather than in the chaos of the last week.'
Lupin received this with the quality he had for genuine things --- simply, without deflecting.
'Thank you, Ron,' he said.
'There's something else,' Ron said. 'What will you do, after you leave?'
'Im considering his options,' Lupin said, with the careful tone of someone who was not lying and was not telling everything.
'You could start a business with sirius,' Ron said. 'Something that uses what both of you actually are rather than pretending to be something you are not.'
Lupin looked at him for a long moment.
'What do you have in mind?' he said.
Ron had been thinking about this since February. Not a single business --- two businesses, with a third thing underneath them that was not a business at all.
'The first part is for you,' Ron said. 'A bookshop and café. Books you've chosen, drinks and food, somewhere quiet to think. The café is the public face --- respectable, calm, nothing to draw attention. The bookshop stock reflects genuine curation: rare texts, good editions, the kind of thing that draws serious readers. You'd run it. It suits you.'
Lupin looked at him.
'The second part is for Sirius,' Ron said. 'A vehicle club. Muggle motorcycles and cars, modified with magic --- the kind of work Sirius did on his own bike, but formal. A workshop and a track, private membership. Invitation only. Rigorous on entry.'
Lupin was quiet for a moment. 'Sirius would --- yes. He would find that genuinely engaging. The mechanical work, the magic applied to it, the community around it.' He paused. 'And a private club has its own social logic. People talk to each other in workshops.'
'Yes,' Ron said. 'That's the third part. Not designed as intelligence --- emerging as it. The right people in a private space, over time, building trust. Neither business requires Sirius to explain his history to anyone. Neither puts you in a position that draws official attention. The bookshop and café is yours. The vehicle club is his. Both run separately. Both real.'
'And both cover the same location,' Lupin said slowly.
'The Diagon Alley end is the front,' Ron said. 'Street-facing, legitimate. The vehicle club would need a different property --- larger, outside the alley, somewhere with space for a workshop and a small private track. Two buildings, linked only in the way that two separately registered businesses owned by the same people are linked.'
Lupin looked at him for a long moment. 'You've thought about the legal architecture.'
'I've thought about the part that matters,' Ron said. 'Sirius needs to stay out of trouble. You need to stay out of attention. The only way both businesses work long-term is if they are genuinely what they appear to be. Good books and good tea. Good mechanical work and a private track. The intelligence function is a consequence, not a design --- because a designed intelligence network has a paper trail and a liability. An emergent one doesn't.'
The practice room had the quality of somewhere important being decided.
'Bring it to him after term,' Lupin said finally. 'Both parts. We'll see what he makes of it.'
'He'll like the vehicle club,' Ron said. 'It gives him somewhere to work with his hands and be genuinely himself. The bookshop part he'll like for you.'
Lupin looked at him with the particular expression he had reserved for Ron since the Patronus had come out as a wolf.
'You are,' Lupin said, 'a very unusual young man.'
'Dumbledore said that to me in January,' Ron said.
'He was right,' Lupin said.
They finished packing up the practice room and walked back through the castle in the comfortable quiet of a conversation that had landed well and did not need more words added to it.