So I was thinking about how Stiles seems to be reaching a breaking point—that final inhale—and how it could push him in two directions. One would be to pull away from everything and try to remove himself from the center of the whole werewolfy world. The second would be to ask for the bite.
Assuming that it was the latter, I can imagine a thousand storylines opening up from that, most of which put Stiles in close proximity to Derek. So taking a happier (and shippier) outlook on that storyline for season three, here are some thoughts that spring to mind.
I imagine that the only thing Derek would say after Stiles asked would be a terse “No.” Nothing else. No explanation. So Stiles might think that Derek said no because Stiles wouldn’t make an asset to the pack. Stiles would then try to prove his usefulness in lots of ways—by getting closer to Deaton and learning more about wolves, by making a list of all the ways he’d saved their furry asses and sticking it on the beam of whatever dark, dank place Derek was staying in. He would show how everyone around them trusted him, believed him. Everyone but Derek.
It would lead up to one big moment, the moment where Stiles finally breaks down and asks Derek why? Why won’t he do this one thing? Why won’t he help Stiles be stronger, better? Can’t he understand that all Stiles wants to do is protect the people that he loves? He should know that better than anyone. And Derek would do that thing with his mouth, the frustrated tightening of his lips, and look away. “Because you’re already enough.” Nothing else. No explanation.
But it would be enough.