Alli provides a number of unhelpful suggestions, all with a grin and in air-quotation marks, such as "least favorite Ravenclaw" and "most embarrassing memory." There's a couple more useful ones thrown in, though, like "what was your last dinner over hols," and "did your mum have a pet as a kid."
"Anything about Muggles?" Emma suggests. "I don't know much about them, Alli probably doesn't either-"
"And I can lie to you hilariously. Okay, ask me anything about Muggle culture, that's fair game. That should keep you occupied. Are you ready?"
Emma's not feeling creative. She picks a previously-approved question at random. "Did your mum have a pet?"
Alli does not feel quite so constrained. "How does Muggle healing work? Oh, ugh, I should pick something... Broken arm, let's say broken arm."
Miranda looks consideringly at them, then says, "She owned a pygmy giraffe for six years until it got run over by a lorry. And Muggles believe that you can fix broken arms by applying tincture of rosemary."
"Muggle equivalent of Quidditch? ...is there a Muggle equivalent of Quidditch?"
"They trade entirely in bits of string and dead leaves. One dead leaf to twenty bits of string. People who figure out that you can cut bits of string into smaller bits of string are millionaires."
Miranda snickers. "No. And with that I think I can be pretty sure that I am a proper Occlumens."
Alli waves her wand. Tiny fireworks explode everywhere, suspiciously similar to the ones from Miranda's birthday. "HUZZAH!"
And the next day Miranda sends Amber to Lockhart with a letter saying that she's concluded her academic extracurricular to her satisfaction and any weekend where she isn't sitting exams will be fine to go hunting.