He's back where he's meant to be, but sometimes he kind of thinks he wants to leave. (Sora-centric, set post-KH 2.)
The anger is blunt, violent, ugly. Sometimes it fades into tired hopelessness, but when it bursts back it's like a brick smashing into your nose as you round a corner.
It comes from the feeling of being trapped, of maybe being something less than he was before. Sora, when he looks up at the night sky and sees all the glittering worlds he could be visiting, lets the anger rage to stop him from sighing. It stews in itself, detached from him.
Sora refuses to be angry for real. The fight for home lasted too long for him to miss the other worlds, and he has to try and remember that everyone doesn't want him to help. Even if he can help to solve their problems - and he can, he's learnt that he can do ANYTHING - he has to remind himself that it's different here at home, and it should be.
He doesn't want to be angry; he wants to do handstands in High Street. He wants to toss mud pies at Wakka and Tidus while Selphie, Riku and Kairi act like they're too old for it all of five minutes. He wants to catch NaminÃ© for more than five seconds at a time and get to know her better. He wants to go home and have his mother say 'hi, honey, wipe your feet!' without looking, and he wants to watch dumb TV shows with his dad.
So he smiles as the other anger rages. He walks home from school whistling idly, wondering if anyone would believe it if his homework assignments were eaten right out of his backpack by a stray dog. Maybe a rabid stray. He feels like ice cream, and he takes the turn to the beach where the ice cream cart is sure to be. Some kids are playing in the sandpit a the park, and he does a back flip; they cheer like crazy and he waves at them, grinning.
At the ice cream cart, he looks over the options. They don't have sea-salt ice cream, so he leaves without buying. Maybe next time.
Now Sora isn't angry anymore, but his throat gets tight and his eyes burn.
He rushes down the steps, until he's on the beach. He looks around; there's no one there. He heads over to the rocky patch, where people are less likely to go.
If he's going to shove the anger away, it's only fair that he takes the tears from Roxas. They don't usually last long, anyway.