Aim and Ignite (Dean/Castiel | ~10k | Read on AO3)
After the angels fall and Cas loses his grace, and with Sam still recovering from the toll taken on his body by the trials, Dean starts a prank war as a way to lighten the mood in the bunker and alleviate his boredom. It might just have some unexpected consequences. ~A post s8 canon au.
It starts, as things often do with the Winchesters, because Dean is bored.
They’ve been cooped up in the bunker for weeks, no hunts, barely any visitors besides Charlie and Kevin who show up every once in a while, and nothing to distract him from the tense air filling the bunker and crushing him from every direction. Sam is mostly back to normal, finally recovered from the trials after a hell of a lot of bed-rest and a timely spell from the Men of Letters’ archives, but pissy since Dean has him under house arrest until he’s sure Sam’s back in shipshape. And Cas—Cas had eventually found his way back to the bunker after the angels fell, pitifully, awfully human and full of guilt so plain you could read it in the hunch of his shoulders and the lines around his eyes.
Weeks pass with Cas wandering listlessly from room to room, radiating self-hate and downing gallons of coffee just to stay awake, and Sam grumpily locking himself in the library or the archives or his bedroom day after day and only emerging to scrounge up something to eat every few hours. So yeah, Dean is bored: he hates research and no one’s talking and Dean’s practically coming out of his skin with the need to do something about his brother and Cas’ foul moods.
So the next time he’s out on a supply run, Dean adds a bag of Oreos and a tube of minty toothpaste to the shopping cart he’s pushing up and down the aisles. He spends way more time than is probably necessary making sure the toothpaste is white and not that sparkly green shit, earning himself a few skeptical looks and trying to look like he has intense tooth-cleaning needs and not that he’s got some weird-ass toothpaste obsession. But by the time he makes it out to the checkout counter he’s friggin’ pumped, and he even manages to exchange some harmless flirting with the matronly woman minding the register, shooting her a wink as he heads out the door with his purchases.