"I'd like to see what there is to be had, it'll be very novel."

"All right." And they can head back out into the street and browse.

There are storefronts and pushcarts and open-air displays of things! There are bits of magical creatures and bits of normal creatures and a pet store with entire living creatures! There's a clothing store full of robes and an equipment store full of telescopes and cauldrons and bags of holding! There's an enormous bookshop and a sporting goods store with a display of broomsticks and an ice cream shop advertising two hundred flavors! There are potions that do everything from making your hair longer to letting you breathe underwater!

Cam doesn't want any pets but he does want to stroke an owl before moving on. He lingers at the bags of holding - are any of them convenient to stick on his belt loops? - and at the potions - he doesn't need one for his hair or to breathe underwater but surely there's something he does want -

Bags of holding are mostly in the shoulder-bag form factor, but there are some that can go on a belt loop.

The potions store has many other options! Would he like to not have any more boils? How about lots of boils? A potion that makes anything it's poured on smaller? A love potion? A potion for dreamless sleep? A potion to replace any of his bones that have gone missing? One that will make him hover a few feet off the ground? Cures for everything from headaches to dragon-pox? Fire resistance? The ability to see sounds and hear colors? Improved night vision? Increased energy? A tendency to find everything screamingly funny?

He'll snag a shrinking potion and a synaesthesia potion and a night vision potion and memorize exactly what the love potion looks and smells like.

This one looks like pinkish gloop and smells sort of like cinnamon and sort of like watermelons, but the signage implies it's a specific kind and other kinds exist. The ones he buys come with little cards with dosing information and how long they take to kick in and wear off.

He reads all the concerning little cards. "These are legal? I'm never drinking coffee I don't make myself again."

"You wouldn't be the first person to have that policy."

"I don't blame them! Eugh!" He shakes his head.

"I suppose the magic you're used to poses a very different set of hazards."

"I mean, I could drug people? But, one, I'm not going to, two, if someone drugs me and it's just a normal non-magical drug it will not work."

"Convenient. But you can still get the benefits of coffee?"

"Yeah, I can let stuff work on purpose."

Lupin nods, looking envious. "Anything else on the agenda before we go back?"

"Don't think so. Thanks for the escort!"

"You're very welcome." And they can make their vaguely unpleasant teleport back to the school.

Gosh, how vaguely unpleasant. Cam rids himself of the coat, flies up to the castle.

Hogwarts is as architecturally grand and spatially unreliable as ever.

He ensconces himself in the library some more.

He can make a sizeable dent in the collection, at least the parts that cover magical history, culture, and zoology rather than practical skills he can't learn, by the time Dumbledore sends him another note. It's vaguely and cryptically worded, but in context it means that Harry has gotten pretty good at Occlumency and they're ready to try to take the bit of Riddle out of his face.

Assuming the note also contains information about when and where they should meet for this, Cam turns up.

That much at least Dumbledore is capable of putting in plain English. Harry is there too, looking nervous in a "let's get this over with" way.

"Thank you for joining us. I believe young Harry is now able to contain the fragment of Tom Riddle entirely within his scar. I hope you will be able to confirm this, and extract it safely."

"Let me check," says Cam agreeably, and he does some very fine-grained conjurations for the that-one-over-there location of Tom Riddle. Any skull or brain inclusions?

Harry shuts his eyes and concentrates, and once he's doing so the Riddlebit includes a little disk of skull but no brain.

"Okay. I'm going to anesthetize you, check again, then stick a string to your scar so I can interpolate and pull at the same time. When I replace the area do you want to keep the scar for cosmetic reasons or no?"