AN: Originally posted on my Tumblr and Pillowfort but figured it's long enough to post here and on Ao3 as well. For those interested, I have the same name on all three sites

"Ne, Reborn?"

Reborn's eyebrow twitches beneath the shade of his fedora. He had only just finished answering Tsuna's million and one questions about his math homework- homework Reborn's now reviewing.

"Why did you agree to tutor me and Dino?" Tsuna asks.

What kind of question was that? "I was contracted," Reborn says. He runs a finger down the careful stacks of numbers until he reaches Tsuna's answer. Sometimes he has to blink and refocus on the numbers; Hermione's rune and arithmancy calculations superimposed themselves onto math homework far too easily.

"Why? You could have said no."

Reborn sighs and drops the papers on the low table. Of course, the bugger wasn't going to drop it! Crossing his arms, he glares up at his student. Tsuna's brown eyes are focused on Reborn rather than his English homework- which is due in the morning and is far more important than this impromptu interrogation!- lying on the table. "I'm a freelancer," Reborn explains slowly. "I take contracts offered to me by various Famiglias and complete them in exchange for payment."

Tsuna scowls, and Reborn resists the urge to roll his eyes. "But, if you're 'The World's Greatest Hitman'," Tsuna air-quotes, "and a freelancer, you're not obligated to take every contract. Even if you're loosely allied to a Famiglia." Tsuna shifts so he's looking at Reborn directly, and for a moment, it's little Colin Creevey with a new argument for getting an autograph sitting in front of Reborn. "So you must have a reason to take tutoring contracts."

"Money isn't a good enough reason for you?"

"There's no way you're making more money staying in one place and taking only one contract for years then if you were taking a hit contract or two every week."

Reborn smirks. Tsuna's not wrong. With his reputation, Reborn could charge as much as he'd like and someone somewhere would still hire him. "Even so, I'm making more than enough money to live a comfortable life tutoring a Famiglia or two's heir," he says. A luxurious one if he added his savings, even without touching his inheritance.

Tsuna sighs and looks to the ceiling. "But there's nothing stopping you from living off whatever money you've saved." Sometimes Vongola's famed intuition is too sharp. It's enough to make Reborn wonder if Luna was related to said mafia family with her ability to see through someone.

Tsuna meets Reborn's eyes again. "Nezu-sensei taught because it got him power and respect. Harada-sensei teachers because she wants to do better than her teachers, and Chiba-sensei teaches because he loves sharing knowledge," he says. His mouth twists into a determined line. "So, why do you teach? Because it isn't about the money."

"If Umbridge refuses to teach us how to defend ourselves, we need someone who will." Twenty-five determined faces flash through Reborn's mind- first year Nigel, sees-too-much grey eyed Luna, can't-meet-Harry's-eyes-for-more-than-a-second Neville, pompous Zacharias, brown-eyes-blazing-teach-us-Harry Hermione, all-too-serious-guys-please-laugh Fred and George, the list went on.

Reborn ducks his head. "I teach," he begins slowly, "because once upon a time, twenty-five children-" because that's really what they were, not young adults, not soldiers, but children and students- "asked one of their own to teach them how to defend themselves because the adults refused to acknowledge the danger. And I couldn't say no." He looks up. "I still can't say no."

Tsuna nods, his eyes downcast. A moment passes. He turns back to his homework. "How do you diagram a sentence again?"

Reborn closes his eyes- this was the twelfth time. He huffs a near silent laugh as he repeats the lesson again. He could do this. Today was simple. Today wasn't a day for teaching defense or politics or how to make simple charms deadly or how to run a Famiglia. Today was for basic, everyday school subjects, and he could do that.