The first thing Benny learns about the human that sent a ripple through Purgatory is that he's hard to pin down.
In more than one sense; if Benny hadn't been able to smell him, he'd lost his trail several times.
But it's even harder to assess what mood Dean's in, if he's liable to get on Benny's case for basically breathing wrong or be utterly indifferent to whatever Benny does or says.
The whole vampire deal probably isn't helping, but hey. Not like Benny can do anything about that. Plus, friendly conversation isn't exactly the reason they teamed up.
If getting out of this hell hole means putting up with Dean's erratic mood swings, so be it. In Benny's book, that means he's getting off lightly.
He doesn't notice the shaking until a week into their, say, partnership.
It's subtle, and Dean's good at hiding it, like a wild animal trying to avoid alerting predators to its weakness, but Benny's been around the block a few times.
He knows the shakes when he sees them.
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