Because I should be working on Blindsided, but I'm lazy and wanted to try for something somewhat subtle. Alas, I think I only managed to be obscure. Spoilers for the Kakashi Gaiden.
Hatake Kakashi did not smile. He told his sensei this once, over tea and shougi, and the man laughed, and ruffled his student's hair. Kakashi hadn't taken well to the hair ruffling; he was thirteen, and had very little to smile for. Obito and Rin had been dead for a year, and he'd been a member of the Anbu for half of it.
("Are you sure?" Sensei had asked, a little sadly. "The first duty of the Anbu is to protect the Hokage. Perhaps you should look into the Hunters, for a few months at least-"
"No." He'd been resolute in his decision. "The Anbu.")
His sensei was the Yondaime Hokage now, and Kakashi always said the title without the honorific, unless he was on duty- "Hokage," he'd say, and pause significantly, leaving space for the unspoken -sama. "You make horrible tea."
"And you say it with such a straight face, too," his superior sighed. "Anyone else would at least pretend to be joking, but not you." The beginnings of a smile curled up in the corners of his eyes.
"I don't joke. And it's true."
"I know." The tiny smile had grown a bit larger, spreading from his strange, clear eyes to the left side of his mouth in a crooked, almost-smirk.
Kakashi ignored the Yondaime's smile in favor of placing a shougi tab; he was going to win this game, but only because his sensei was letting him win.
Yondaime lost with a graceful nod, and then proceded to beat Kakashi into the ground for the next three games. When Kakashi glared at him, he merely shrugged and said, "Turnabout is fair play, Kakashi-kun."
Kakashi's glare could have killed a lesser man, but his sensei only smiled- a real smile, not a hidden half-smile.
He smiled with his whole body sometimes; Kakashi still wasn't sure how he did it. He'd seen his teacher snap men's necks without hesitation, seen him kill dozens of people without remorse. Yondaime had lost precious comrades and students, seen them brutally murdered before his eyes- but at the end of the day, he could still look at Kakashi and smile that stupid, amazing, blinding smile, as though it were nothing at all- and Kakashi supposed it wasn't, not really.
Kakashi wondered if his sensei would still smile like that if he died. He wasn't sure why it hurt so much to think that the older man probably would.
"Cheer up, Kakashi-kun. You can't win them all." His old teacher poured more of the mediocre tea while Kakashi cleared the board again.
"I will eventually." He was a genius, wasn't he? Kakashi removed his mask to drink the tea; it wasn't something he did very often, now that he was a jounin. In fact, his sensei was the only person to have seen his face in months. "Right now, it would help if you stopped cheating."
His sensei laughed, completely remorseless. "You're breaking my heart, Kakashi-kun." He won the next game, too, and didn't cheat. Kakashi thought sourly that if the man was trying to prove a point, there were better ways of doing it.
He still thought so, several months later. Kakashi stood before the memorial stone, wearing black, with his hands in his pockets and his mask firmly in place. It was a beautiful autumn morning, and the leaves were in full color, rippling like fire in the breeze.
He still didn't think turnabout was fair play, either. His eye slid over the old, familiar names on the memorial stone and settled on the newest one.
He didn't think it was fair, at all.