He feels an open summons and lets it grab him -
"In the sink, please. I also have some unfortunate news to deliver. While Sherlock was in New York, he discovered that the car crash that killed Tony's parents was engineered by a family friend. Tony is not handling the news well; you might not see much of him today."
"Sherlock is still likely to want to meet with you later; I'll let you know when he asks."
"Sure. I'll just go continue fleshing out my to-do list, shall I?" Back to the lift he goes.
Cam to-do-lists. He opens the window and makes another batch of bees to break up the monotony. He asks Jarvis the occasional question about whether and how magic has interacted with the suspiciously matchy history of this world.
"Sherlock would like to speak with you now. Shall I tell him to come down?"
Cam puts his computer in standby and stretches. He's going to want to go out some night and fly around, he thinks, but nothing urgent.
"Hello," he says, not in Tony's accent.
"Correctly deduced. I'd say pleased to meet you, but I am not pleased about very much today."
"Yeah, Jarvis told me there was a displeasing bit of news going around on top of the unexpected daeva."
"Yes. To complicate matters further, the man who had Tony's parents killed is currently running Tony's company for him pending Tony's eventual completion of an engineering degree. I've no doubt he's going to try the obvious follow-up if he can't get Tony to give up the company any other way."
"...Tony's parents," says Cam, raising an eyebrow at this extremely Tony-resembling person.
"Ah, of course, I have failed to introduce myself. Sherlock Holmes, clone publicly masquerading as twin. Would you like that story too, while we're here?"
"...Sure, can't hurt. This world is disturbingly similar to mine as far as Wikipedia's concerned for having AIs and vampires and clones, oh my."
"One AI and one clone, to my knowledge," he corrects. "Both byproducts of Tony's intensely lonely childhood. He cooked me up when he was twelve, I caught up to his development when he was fourteen, and in between he had very little idea of what to do with me and consequently ignored me as much as possible. So I grew up on literature and Jarvis and acquired a name from the former since the latter was at a loss on the subject."
"And now here you are. Okay then. Do you have a use for demonic help with the assassin? Tony already summoned a fairy, so you can maybe retrieve him with added snazzy magic powers if all else fails if it works like that, but this being a brave new world that has such people in't I'm not sure I can vouch very confidently."
"Ha," he says. "Yes, I'll be wanting to do one of those myself before too much longer. Do you care to provide cookies?"
He heads down the hall in full expectation that the elevator will be waiting for him when he gets there. It is.