"You'll catch up."

"I'm trying."

"I can help you out if you have trouble spots as long as I have time."

"Thanks. I don't like imposing on people, especially not with things a pureblood witch would know -"

"It's okay, I'll shoo you if I'm too busy so ask whenever."

Nod. 

She finds Miranda with a list of questions a few days later. What are house-elves, what's a good thing to read to know all the important families, what's something written with simple words that explains dark magic and what it can do and why people whisper about it, what's wrong with her Wingardium Leviosa...

House-elves are a species of magic slaves, they like it that way it's weird if she promises to respect that Miranda will tell her how to get into the kitchens. Bloodlines and Origins is pretty readable and you can also assume any two purebloods whose families have been in Britain long enough (so, not Miranda, not the handful of kids from India) are related and ask them how as small talk. Dark magic is magic that requires evil intent and there's not really any simple books on it but here's the rundown of the unforgivables. She's swishing wrong, borrow this demonstrative stick.

" - does Occlumency also help with the Imperius -"

"It can't hurt but I've never tried it."

"Do people have to worry about that -"

"The Imperius is insanely illegal and practically nobody learns it, let alone casts it, anyway. If you're worried about it I have a way to tell if you're under it or not and I can check you now and then, but I doubt Black can cast it and if he can I doubt he'd escalate like that with you."

"Thank you." She gets to practicing Wingardium Leviosa.

Black uses a spell to throw her against the wall whenever she can be construed as in his way and ignores her otherwise. 

Well, that's - navigable. Miranda can heal well enough to save her trips to the hospital wing over minor blunt force trauma.

She gets plenty good at staying out of his way.

Miranda helps her out where possible and attempts to think of opportunities to get Black to cut it out altogether.

Minor stays up until outrageously odd hours for a week and then declares he thinks he knows exactly what is wrong with the wards and how to fix them, though maybe it should be tested somewhere smaller than Hogwarts because recasting all of the wards on Hogwarts will require most of the experts in magical Britain and actually even they might not be able to do it. "Though I think they should try," he tells Karen, "this is really important."

"Is electricity actually useful for anything yet?"

"Not yet but it's only a matter of time and interactions with magic should be figured out now!"

"What if in fifty years they're using some totally different kind of electricity and the first kind was never useful and the interactions are different?"

"It's not like that, there aren't kinds."

"No?"

"There are things you can vary but the wards disallow all of them and the interactions might be different but that's why we need to start testing!"

"We? Do you need me to do something?"

"Help me convince Hogwarts to go along with it?"

"I'm not very persuasive."