"It varies."

"Yeah. I guess it could show me myself dead? But since I would be conscious and looking right at it I don't know if that would be scary so much as disturbing."

"Or perhaps it will show you something that you might expect to kill you."

"If it gives me a Dementor does it just look like one or feel like one too, do you know?"

"It did a remarkably lifelike dead Tony. So to speak. I don't know if it can mimic the effect of a Dementor."

"Maybe I should ask the teacher ahead of time just in case."

"Probably a good idea."

"What do you do with them after they turn into things?"

"Laughter repels them. There is a spell that will alter the Boggart's form into something more humorous, and then you have a good giggle and it tries to run away and the next person has a go. I did not successfully cast the spell."

"I wouldn't think most sincerely terrifying things would be very funny," objects Bella. "That doesn't make sense."

"And yet, there it is."

"I don't think I'd be scared if I saw a very convincing image of myself dead and knew full well what was going on. But I don't know what I'd do to it to make it funny, either. And I know I don't function very well around a real Dementor but if the boggart is bad at faking it I guess there could be something funny that could happen to it."

"The teacher recommends party hats," he says dryly. "As a catchall. They looked particularly fetching on the giant spider."

"Corpse in a party hat," muses Bella. "No, I think if I had that to work with I'd make it look like I'd died cartoonishly. Put it under an anvil, tongue sticking out, X's for eyes, about to pop back up as soon as the plot demands. Dementor I think I'd put in tie-dye."

At that, Sherlock actually does giggle.

"Death to good taste," intones Bella, holding a clawing hand out at him. "I will suck out the soul of fashion sense."

He snickers.

"Thank you for warning me," she adds more seriously.

He shrugs. "Of course."

"I assume you already warned or are about to warn Tony; I can tell Feral if you haven't."

"Yes. I have warned Tony, but not Feral."

"- Is this why you weren't in Charms?"

"Yes."

Bella hugs him again.

Hugs.