"Alright, Cas. Come on out to the car for a second," Dean said one Saturday morning.

"Are we 'testing the durability of the backseat' again?" Cas asked hopefully, air quotes included.

"Not quite. Come on, I'll show you." Once he was behind the wheel with Cas in the passenger seat, Dean turned the key but didn't start the engine.

"What's going on?" asked Cas, as Dean flipped on the stereo and pushed in the tape that was there.

"It's time you got a little musical education," Dean said. "I don't know how to work any of the crap on Sam's laptop, so tapes are what we got. Now: what does this sound like to you?"

"Loud and inarticulate, mostly."

"Okay, well it's Metallica. One speed only." Dean stopped the tape and popped it out of the deck. "You wanna open that for me?" He pointed at the glove compartment. Cas pulled the box open to reveal a stack of cassette tapes in plastic cases, each one labeled with a different band. "Pass the Aerosmith." Dean slid the tape into the stereo. "How 'bout now?"

"The vocalist does have quite a range."

"Meaning?"

Cas sighed. "I miss Jason Derulo."

Dean hit the eject button. "I can't believe I'm having sex with you. Pick another one."

"Which one?"

"Doesn't matter. Anything's better than having to sit with that little fun fact of yours." Cas shoved in a tape at random. "Ah!" Dean lit up. "Okay, this one you gotta love. It's a house rule."

Cas stared out the windshield. "It sounds like..."

"Shh! Don't talk, just listen."

After about fifteen seconds, Cas went, "I don't understand what's supposed to happen, now."

"Are you kidding me? The chorus is coming, you're supposed to feel it!"

"I don't feel much of anything beyond befuddlement."

"Feel it in here!" Dean said, tapping Cas' chest for emphasis. The song played on. "Ugh, I mean, that riff right there? Come on."

"I far prefer a classic boy band anthem, myself."

"Oh my God, you're worse than Sam. For ten years it's been nothing but Death Cab for Cutie and weird Scottish bands who keep using the weather as a metaphor for everything that sucks."

"I'm not following," said Cas.

"Obviously I gave up on my brother a long time ago, but it's not too late for you!" Dean stopped the tape. "I wanna die knowing I did everything in my power to give this family some culture."

"Have you ever tried listening to popular radio?" said Cas.

Dean made a face. "Ugh, no, never. Do I look like I was born in a Banana Republic?" Cas flipped on the radio and turned the dial. "Cas, no. Cas, no." Dean repeated this several more times, in an increasingly loud and panicked voice.

"You might enjoy it," Cas said patiently.

"Yeah, just like I might enjoy getting four root canals at once," Dean said. Cas settled on a station.

"Now, let the manufactured drum noises just... wash over you."

"I am dead inside," said Dean. "What is this?"

"It's referred to as dubstep, and is considered one of the indicative genres of the current decade."

"Well, it sounds like someone snorted twelve lines of cocaine and then went, 'Yeah, ya know what? Music: I'm gonna go for it.'"

"Maybe we're going to have to agree to disagree."

"We can agree that this was a terrible decision," said Dean. The song on the radio faded out, and the DJ said a few things about some pop star who was bringing her tour to Kansas City that weekend, and then the next song started as something shifted in the air.

Later that morning, Sam found Cas in the library. "So… what'd you do to my brother?"

"Which time?"

"Ugh, no. I mean… he's singing Top 40 in the shower. And I kind of assumed we'd prevented the Apocalypse, so if you've got any intel…"

"I don't know what you mean."

"Cas, I just heard him do a whole rap. Verbatim."

"I may have… expanded his musical horizons."

"Yeah. Well it's terrifying."

"Mornin'," said Dean, appearing in a towel. "Hey, we goin' out for breakfast?"

"Depends," said Sam. "When does your tour bus have to be back on the road?"

"Shut up. I'm tellin' ya, some of that pop radio crap ain't that bad."

"This is your fault." Sam said, pointing at Cas.

"I'll gladly take credit where credit is due."

"Alright, whatever. Dean, get dressed. I'll drive. Last two in the car have to put up with Coldplay."

"Coldplay is the devil," said Cas.

"What have you been telling him?" Sam rounded on Dean. "Their Parachutes album is considered one of the most well-crafted, critically acclaimed… you were just rapping! How is Coldplay the thing we're talking about right now?"

"Shut up and let's go eat pancakes, Sammy. I promise I'll only rap the entire way there."

"And I will beatbox," said Cas.

"And I'll drive us into a ravine," said Sam.

"Well if Cas and I make it out alive, then I'll make sure we play Death Cab for Cutie at your funeral," said Dean.

THE END