Dean knew he should’ve ordered that second cup of coffee before they left the diner, but he was determined to reach the bunker tonight, and the longer they’d sat in the booth, the more tempting the adjacent motel’s neon vacancy sign had started to look. Ignoring Sam’s suggestion that they check in for the night, Dean had signaled for the check. He’d filled his quota of burned motel coffee for a few dozen lifetimes.
He’d thought he was fine to drive–he’d gotten six hours last night after Cas insisted on rubbing his back–but with each mile, the monotony of the flat highway crept into his brain like fog, that out-of-body sensation that comes only with bone-deep exhaustion. He operated the car by muscle memory, spacing out between mile markers, and rubbed his eyes. If he could get them to water, that might revive him, but they were dry as charred bone. Normally he’d turn on the radio, but Cas was dozing in the back seat and Dean knew better than to wake him, since a sleep-deprived Castiel was only endearing in twenty-minute sprints.
Sam, though — Sam didn’t get off so easily. His head lolled against the passenger’s side window and his eyes were closed, but he repeatedly swept his tongue across his teeth in a manner that told Dean he was still awake.
“What is it?” Sam yawned and belatedly covered his mouth. He pulled himself upright. “You want me to drive?”
“Just talk to me. Everything’s starting to look the same.”
Sam looked thoughtful for a moment and said, seriously, “Actually, something’s been bothering me since we left the diner.”