Based on the song Guilty by Blue.
Jackson doesn't always see the reaction that his snide remarks cause. He doesn't want to, because, in his head, it's just another reminder of how insignificant, how useless, he is. But he sees Stiles' reaction. He sees it and he hates himself for it. Stiles wasn't even meant to overhear it. He thought he was elsewhere. But he's heard and now Jackson has to fix things. He has to go after Stiles because his stomach is churning and roiling with guilt and he can't not say sorry for this. He can't forgive himself for hurting Stiles, but he needs to make sure that Stiles understands that he is sorry. So, he goes after Stiles, completely against the orders of Derek, but he doesn't care.
He follows Stiles into the forest. He can smell his scent, it gives him an advantage over Stiles. But still, Stiles isn't in sight, and he can't hear him. Jackson's starting to get worried. Stiles is never this silent.
He finds him at last in a clearing in the middle of the forest. "Go away, Jackson." Stiles says.
"No," Jackson refuses to go. He came here to apologise and he is going to apologise whether Stiles likes it or not. "Look, Stilinski... I'm sorry. About earlier." Stiles laughs, harshly, hoarsely.
"No, you're not," he says. "The number of times I've heard you say something bad about me. You never apologised for any of them. What makes this time any different? Maybe the fact that you know I heard?"
"Stiles... Please, believe me. I'm sorry!" Jackson is pleading. He knows it, he can hear it in his own voice. "I didn't mean it."
"Then why did you say it? Why did you fucking say it?" Stiles is shouting now. "If you really didn't fucking well mean it, why say it? Just another opportunity to put the idiot human down, was it?" Jackson shakes his head, wanting to deny it, but he doesn't know why he said it. He doesn't know why and he wants Stiles to understand that. But Stiles is shouting and sobbing now. So, Jackson does the first thing that makes sense to him. He kisses Stiles, to shut him up. Stiles shuts up. "I don't know," Jackson says. "I don't know why I said it when it wasn't true. And you're not an idiot human. You're probably the most useful pack member. And you're not even a wolf!" This makes Stiles smile slightly, but there are still tears running down his cheeks. Jackson wipes them away with his thumb. He kisses Stiles again. Stiles kisses him back. "Do you hate me?" Jackson asks in a small voice, "For saying those things." Stiles frowns.
"I don't think I could ever hate you, Jacks." The nickname makes Jackson look at him. Stiles smiles, practically reading Jackson's mind as he asks, "Like the nickname, Jacks?" Jackson smirks, now back to his normal cocky self.
"I dunno. Maybe you could, y'know, get me used to it."
"Course," Stiles says. "You free tonight?"