how they deal with anxiety:Arvie is anxious most of the time, and has a problem of overthinking things. Friend hasn't messaged back yet? nope. they're dead.
probably got into a wreck.
Walking in the park, "How many ways can i possibly die in this very moment?" Thinking through every possible scenario, he always manages to find the worst in any situation, and most of the time it greatly upsets him, which really it would upset anyone. That's his biggest problem to face everyday, and really every night. sometimes overthinking these things can make him paranoid enough to avoid sleeping, and a good nights rest is a nice thought, but something he hasn't seen in a while.
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Still, although he can't get rid of the thoughts
completely or erase or challenge his anxiety, there are little things he can do to cope with it.
"A hot shower and cold ice cream can fix anything"
Something he says a lot, and to him it does fix a lot. if he's at home, it's nothing to put on some music and step in a hot shower. granted, he does do a lot more thinking in the shower as well, but music plays as a distraction and he has the time to think through these impossible scenarios to find the impossibility in them, to calm him down. Ice cream. doesn't help his anxiety much, but is nice when he's upset.
Out and about however, a hot shower isn't always available, nor is music appropriate in every situation. Arvie is a big fan of science fiction, and he has a problem with fidgeting when anxious. he'll mess with anything in his hands, pluck at clothes or pull at his tail or hair. to deter the more self destructive behaviours, he carries a coin.
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A Bronze coin who's blue paint is almost completely worn off. Depicted on it, is the hitchhiker's thumbs up, and on the other side the raised words "DON'T PANIC"
He received the coin at the first small convention he went to. he doesn't like talking to people much, or going out in crowded places, but in the moment when he got his book signed, and was given the Hitchhiker's Coin, there was a moment of calm. he laughed and talked, albeit nervously, but he enjoyed himself, and the coin is a nice reminder of the good things that can happen too.

Rubbing the coin helps keep his hands busy, tracing his fingers over the words "DON'T PANIC" reminds him of that message. it also give him more to think about. alternate plants and universes. universes where whatever he's thinking won't happen, or will happen.
The coin reminds him of that escape and calms him down, giving him the opportunity to think more about other places and what might happen there instead of the bad that might happen here.