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This was not the job Dean had trained for all his life. It was amazing just how quickly time travel changed everything. Instead of spending his days fixing cars, hunting, and looking for hookups, he spent most of his time on the time machine he and his brother had built, taking people on guided tours.
There were two types of time travel. One of them was incredibly complicated. It required years of specialized schooling before you could even get a learner’s permit and go on trips with a licensed agent, and then more years of school and apprenticeship before you could get a provisional license. The trips were incredibly difficult to calculate, but you could actually change history. People who went that route often got lost in time and space, living out their lives in a very different timestream than most people.
The other kind, the kind Sam and Dean ran, was more like visiting the world’s most interactive, authentic VR museum. You went back to the time and place of your choosing, or ahead, and you could interact with the people and animals, but when you left, all traces of your presence disappeared as well. If you went back in time and killed your own grandfather before your mother was conceived, it didn’t matter, once you went back to your own timestream your grandfather would pop up alive and well and it would never have happened.
Sam had found a loophole, though. If you went back to the same person, they would remember you the next time they saw you – and the more you went, the stronger the memories. Sam had tested that by visiting his ex-girlfriend Jess frequently. He couldn’t save her from the fire that took her life, but he could get more time with her.
Dean’s first intertemporal lover had been an accident. He had five days in a row of people asking to go to Louisiana during the Civil War, and since he had some idea of the place after the first visit, it was just easier to go back there. He started the tours, but by the third day, Benny Lafitte was ending them. On the fourth day, Benny turned the tourists loose in town and then took Dean to his house. “Time travel, huh? Y’know it sounds crazy, don’t you?”
“And yet, here I am. It sounded crazy when I was a kid, but then some genius team worked it out. Not surprisingly, once the prototypes were up and running, it kinda took off with a life of its own.”
“Yeah. Wow. You, uh, gonna be coming here often?”
“Probably, but you won’t remember me between visits, Benny.”
“Which sucks, but I can deal with that. I’ll remember you when you’re here.”
“Think it’s only fair to warn you you’re gonna get married, then.”
“How do you know?”
“Looked you up on census records when I got home yesterday. You’re gonna marry some chick named Elizabeth and have at least four kids.”
“Lizzie Theriot?”
Dean shrugged. “No idea. Point is, you think it’s fair to Elizabeth or Lizzie or whoever she is for you to have a guy on the side you don’t remember anything about?”
“You told me yesterday that it don’t matter what happens when you’re here, once you’re gone I’ll remember things the way they were supposed to happen. Is it really happening if it’s only real part-time?”
It had taken a few more visits, and meeting Lizzie Theriot and finding out she saw it Benny’s way, before Dean was comfortable with it. After that, Dean started visiting whenever he got the chance. Sam teased him about his part-time boyfriend, but the truth was, Dean was happy.
Then it was a run on the 1920s in Chicago, where Dean met Eliot Ness. Once he was done fanboying, he realized he had a problem. How do you say, to one of your big goddamn heroes, “No thanks, I kind of have a boyfriend about sixty years ago?” But after the hesitance to get involved with Benny because of Lizzie, it sure didn’t feel right to just get involved with some other dude.
Of course, Eliot was going to be married, too. Eliot had provided the obvious solution – “I don’t get married until 1929, you said. So visit me before then. It’s not cheating if I’m not married. You have a time machine, you can come to whenever you want.”
Benny thought he was an idiot for even worrying about it. “Hell, I don’t remember you exist unless you’re here with me, you do whatever you wanna do out there. You can tell me about ‘em if you want to, but no reason you need to.” Eliot shared that opinion, so Dean decided to take that as policy. They had a good point, after all.
When Dean met Samuel Colt on several consecutive trips back to the Old West, he didn’t hesitate. Sure, theoretically, there might be a chance Benny and Samuel could meet each other, but what were the chances? Same logic for Rosie Holt, in the late 2030s. That one he wrestled with a little more, because that meant she was alive in his own time, but what were the chances they’d ever meet? Rosie was some kid in Iowa. It’s not like he knew her or was planning to go look her up in his own time.
But the weirdest one? That had to be Castiel. That was a trip he made just him and Sam, traveling back to see how far back they could go, and they watched the first fish crawl out onto land. Some sort of glowy being nearly stepped on it, but was stopped by another glowy being. Then they both turned to stare at the time machine.
Angels were a real thing, it turned out. Castiel returned with a human body, and he stared down Dean and Sam. “What are you two doing here?”
“Time travel. Testing our machine’s limits.”
“This shouldn’t be possible. You shouldn’t be able to go beyond the time that humans have ruled the Earth.” Castiel examined their machine, squinting hard at Sam’s calculations. “Which of you pilots this device?”
“Sam does the calculations, I do the flying,” Dean said. “Why?”
“Hmmm.” Castiel reached out and touched both of their foreheads. “I see. We’ll be seeing each other again. Return to your time.”
They quickly discovered that, on occasion, they’d feel called to explore beyond the traditional realms of time travel – most travel guides stuck to recorded history. Every guide Dean talked to said that they wanted to go see dinosaurs, but never could figure out how to get there. There seemed to be a limit to how far forward they could go, too – only a hundred or so years into the future. What’s more, no one else had figured out the memory trick – and when Garth said he tried it, it didn’t work for him.
Sam came in and slapped some papers down. “Let’s go see dinosaurs.”
“We can’t.”
“We can. Just program this in and hold on tight.”
Dean had shrugged – worst that happened was they got into some bizarre time-space warp and ended up right back here the same instant they left. They didn’t. Dean found himself staring down a triceratops.
Then Castiel was there, stopping the triceratops from ramming the time machine. “You two again.”
“Castiel. You gonna explain what’s happening this time?”
Castiel nodded. “You two are… special. As long as you’re together, you can go anywhere you like, anywhen you like. Because you can tap into an ancestral tie to the angels. Way, way back in your lineage, you’re the descendents of two of the most powerful Nephilim ever created – the son of Michael, and the daughter of Lucifer. The power passes to only one person in each generation, and if those two people find each other, they become extremely powerful together. It manifests differently each time it happens, but you two – this is the first time Michael’s heir and Lucifer’s heir have been brothers since Cain and Abel.”
“What’s that mean?”
“It means that you can explore time and space as much as you like with your machine, as long as you remain together. Alone, you’re limited to the usual constraints.”
“We gonna keep running into you?”
“Yes. Any time you go beyond normal limits, an angel will be there to make sure you don’t get into a situation you can’t survive, and I’m the one who’s been assigned.”
“Is this also why people can remember us?” Sam asked.
“Yes. That one, you don’t need to be together for.”
It nearly caused a rift between the brothers when they realized they were both falling for their guardian angel. Castiel came to them in their own time, for once, to smack them both upside the head. "You two both have multiple lovers across time, is there a reason you can't share?"
"It's a little... incest-y?" Sam said.
"Not if it's not at the same time."
"You said we had to stick together."
"When you're flying your ship, yes, you do. When you're out and about and exploring what you're seeing, you can split up. One of you can go off with me while the other explores. Then we can trade, or however you want to do this. Just don't be silly and fight over me."