the_debt_of_time

Then, the boggart of Sirius raised his wand with a vicious smirk. As the robes came
up over his arm, Mia saw the outline of something dark and black against his skin. She
gasped, realising immediately what it was, but she had no time to say or do anything as the
boggart silently mouthed, "Avada―"
"Riddikulus!" Professor Prewett shouted, and the boggart exploded into a thousand
wisps of smoke.
Sirius stood there, staring ahead with wide, terrified eyes.
"I'm sorry, son." Professor Prewett shook his head. "Boggarts do not have the
ability to cast spells, but... Habit I suppose, defending against curses."
Mia rushed forward and flung her arms tightly around Sirius who, unlike Remus,
immediately held her against him, burying his nose in her hair.
"You boys did good work today. I'd like to work with you individually on a few
things. I think it's important. As for you, Miss Potter, I'll be on the lookout for a new
boggart so you can finish the lesson. In the meantime, I hope you're able to talk about
those nightmares to someone. It's not good to let fear fester."
"Thank you, Professor," Mia said, though she certainly did not mean the words.
As soon as the three left the classroom, Sirius muttered, "Mia? What was your
boggart going to be?"
She did not want to tell them, but they had both opened up, letting her see the
weakest parts of themselves: their deepest fears. Fears she knew were unnecessary.
Remus was not a monster, and Sirius was not a Death Eater. But she could not help
but frown, knowing their eventual fates. Remus would, in fact, be labelled a monster, cut
off from society and forced into poverty because of his affliction. Sirius would eventually
be labelled a Death Eater, framed for the murder and betrayal of his friends. Their deepest
fears would haunt them for years to come.
"My boggart would have been the two of you," she said, "telling me how much you
hated me."
Sirius and Remus had equal looks of confusion on their faces, and she could tell
they thought her fear was stupid.
"That's.. ." Sirius began.