Okay, so here's some recommendations on ao3 that match the requirements:
Complete spin off after season 2, but does have season 3 and so on elements.
Stiles feels forgotten, he feels left out. So he does something about it, while getting reacquainted with nature he stumbles on to something else. If the pack doesn't need him, if his dad wants him to stay out of it all, well, maybe he just needs a distraction in the form of 3 adorable wolf cubs!
Hold the Day by Daisyapples
Derek froze, fear and anger battling inside of him.
“Personally, I’m very protective of the things I love,” Argent continued. “But that’s something I learned from my family. And you don’t have much of that these days. Do you?”
“Wow, man.” Stiles suddenly rounded the petrol pumps and put himself between Argent and Derek. “Low blow.”
It was almost amusing to see how put out Argent was; he shifted on his feet, hands clenched into fists as if he wanted to hit Stiles. Derek wanted to grab the boy and put him behind him but he also liked having a shield between him and the hunter.
“You know who this is, right?” Stiles gestured wildly, almost hitting both himself and the Camaro. “Little orphan Annie here lost almost his whole family in a house fire. You wanna learn a bit of tact?”
Derek was almost amused at the boy who had just called him little orphan Annie preaching tact.
The House That Wolves Built by LuneFaitLeFolie
"Stiles isn’t stupid. He knows well enough that the pack are done with him. He knows he’s useless, and broken, but it still hurts."
"Derek is running through every interaction he’s ever had with Stiles, trying to figure out which ones he could have caught Stiles with his claws. The unfortunate reality is that he loses count of how many times he could have. "
Stiles is pushed out of the pack as his injuries render him useless and unhelpful, and the pack start to hate him. He hasn't spoken to them in months, until an allying pack comes to visit and he gets dragged back. But do they really hate him? Or was it all a big misunderstanding?
Blindsided by AClosedFicIsNeverRead
Derek exhaled tremulously and tried to stay calm. He called several more times, growing steadily more frantic each time, before allowing the truth to settle in:
“No. No, no, no, please, no,” Derek whispered to himself, barely able to see the screen through his tearful eyes.
What had he done? Had he been so blinded by rage that he dismissed Stiles' call for help?
Fuming over Scott's betrayal, the Alpha is out of his mind with anger. When he receives a call from Stiles in that incredibly inopportune moment, he does not even let the teen speak - just screams at him, blames him for everything, and hangs up.
But then Erica and Boyd show up, frantically insisting that Stiles is out there somewhere, likely hanging onto life by a thread after being tortured for hours...
Will they be able to find Stiles before it's too late?
And just how much of the Stiles they know will be left if they do manage to track him down?
How Derek's Brain Works by Warlock_Nerd
After looking at Derek’s childhood medical file, Stiles finds out that Derek was diagnosed with Autism at the age of eight.
So in Stiles Stilinski fashion, he dives into research on how to help understand Derek’s condition and also help Derek understand it himself.
Three Little Mistakes Was All It Took by LadyArinn
Stiles' life fell apart so quickly and efficiently that even as he was left absolutely crushed and devastated in the aftermath he still found himself somewhat impressed by the utter effectiveness of it all.
Go Away, Scott by HelloWhyTheFuckAmIHere
After the incident at the warehouse, Stiles is fed up with Scott. He finds himself drawn into Derek’s pack and in the process, drawn to Derek himself.
With the Alpha Pack closing in, Derek needs to learn how to trust his pack and those around him. And who better to help him than Stiles?
Can't rely on me by Littleredridinghunter
Set at the end of season 2, Gerard beats Stiles up, but it's a lot worse than anyone knows.
The pack let him down, that's not really a surprise lately.
When Danny finds Stiles nearly bleeding to death the next day it's the start of a beautiful friendship.
Can the pack make amends before it's too late? Will Stiles ever forgive them for not being there for him when he needed them the most?
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