AUTHOR'S NOTES: An attempt at a "fix the tragic past" for Gintama, although the characters still might not have made it through unscathed - but had things happened this way, they would have had more of a fighting chance.
Many thanks to Plipdragon on AO3 for helpful suggestions that made the fic better! More concrit and other feedback much appreciated!

Disclaimer: Hideaki Sorachi owns these characters. They are used here without permission for non-profit entertainment.

"I'm sorry, I couldn't, I tried..."

The young man's hands are shaking around the cup of tea Katsura has just handed him. His white hair falls into his eyes. On the floor beside him is the hat he was wearing. "I was supposed to..." His breathing is uneven; he pauses to wipe the sweat out of his eyes.

Gintoki and Takasugi are, Katsura thinks, uncharacteristically silent, both sitting crosslegged on the floor by the wall and watching the unknown visitor closely, arms crossed over their chests. Even more unusually, they've saved a spot for Katsura in the middle (where he tends to end up anyway). He sits down properly, knees tucked underneath him, putting his hands in his sleeves to keep them from fidgeting.

Shōyō-sensei looks calmer now, but not as calm as usual, and he's not smiling. Just a few minutes ago, when they saw the stranger in front of them by the house's entrance, he froze to the spot, eyes wide, far more shaken than Katsura has ever seen him before. It was very - unsettling - to see. (Katsura is thirteen now, and shouldn't use words like "frightening" too easily, like a child.)

Sensei is giving the visitor his complete full attention; it's almost as if he's forgotten the three of them are in there as well.

"Take it easy," he says in a low voice. "Don't forget to breathe." He puts a hand on the visitor's shoulder, waiting while the other drinks his tea. The stranger looks like he's trying to hide his face behind the cup.

Finally, the stranger lowers his emptied cup and puts it back on the table, showing those tired dark-ringed eyes again, and the scar on his right cheek. Sensei removes his hand gently and sits back down.

There's a look of aching despair on the stranger's face, more naked than adults would usually show. "I'm sorry, Shōyō-san," he repeats. He clears his throat, seems to make an effort at pulling himself together. "This whole time, I've been with the Naraku. I went back to them. I wanted to protect you from them... But I can't do it anymore." Unmindful of the presence of the boys in the room, he drops his head and says, in a small voice, "I felt that I was going to break."

Katsura holds his breath, and he sees Gintoki clench a fist beside him. Takasugi turns his head to watch Sensei, and the other two follow suit.

Sensei has a look of pain on his face for a moment, then breathes in slowly, and out again. "You did all that for me, all this time," he says wonderingly. "I'm the one who should ask for forgiveness."

The visitor buries his face in his hands, shakes his head back and forth. "No, no, no, no, no..." And then he looks up again, suddenly, meeting Sensei's concerned eyes. "But they'll be coming for you. They will, sooner or later. I'll do my best to defend you... But I think you'll have to fight as well." He glances at the three of them, and then out the window. "For these ones, and your other students. For your... Shōka Sonjuku. If you won't do it for yourself."

Shōyō-sensei looks at him closely, for what feels like a long, tense moment. Then his face relaxes, and he finally smiles. A small smile, but a real one.

He leans forward and puts his hand over the other's. "If that is truly the case, and if we can't run away, then I will, Oboro. But only if you agree to become one of those students I'll be fighting for again. As you should have been all along."

The light in the young man's widening eyes is like a star, shining.