Loki's visits become a weird, irregular sort of routine, like he's a pen pal who occasionally stops by to visit in person. Steve never knows when Loki's going to show up, days or weeks or even a few months apart (the time in between often works out to years for Loki, although he never looks much older). Loki brings treats from Asgard most of the time, usually something richer and more filling than the snacks Steve's mom can afford, especially after the banks collapse. Steve introduces Loki to his favorite comic books and radio shows, and although Loki handily beats him at card games and tafl most of the time, Steve gets good enough that he wins sometimes too.

There are definitely advantages to having a mage for a friend, even if he's only around part of the time. He creates images of Asgard to show Steve his home, and sometimes he's able to magically repair toys and things that Steve can't replace and hasn't figured out how to fix. In 1930, when Steve proudly tells him that the new Chrysler Building is the tallest in the world, Loki's magic lets them sneak inside unseen, all the way up to the top where it's open to the wind and the whole city is spread out below them, stretching to every horizon. When they get caught on the way back down, Loki's magic gets them out of that too, helping hide them until the security guards have passed, which is exciting in a pretty different way. At various points, Loki teaches Steve some sleight-of-hand tricks he's learned, the closest thing a non-mage can come to actual magic. Loki knows a lot about lockpicking, too, which is something else Steve thinks he should feel guiltier about than he does.

It's nice, just in general, having a friend.

When Steve is 12, he meets Bucky for the first time, because apparently being noticed in back-alley fistfights is the only way he can make friends. Bucky actually backs him up and helps him chase off the bullies, something even Loki didn't really do, which Steve chooses not to emphasize when he tells Loki about his new friend.

"Should I be jealous?" Loki asks—lightly, but with an undercurrent of something else that makes Steve frown.

"Why would you be?" he says. "You have friends back home too, right?"

"Of course," Loki says, his expression going slightly stiff, and Steve remembers what he's said, about Thor and his friends. He'd sort of assumed…but then, Loki's never mentioned anyone else. Maybe he really doesn't have other friends.

"I don't really have any friends here," he admits. "Just Bucky now, I think. There aren't a lot of kids in my neighborhood to begin with, and most of them—" He shrugs. "They're jerks and they like picking on younger kids. I don't want to be friends with them either."

"Thor seems to have no trouble making friends," Loki says, very neutrally.

"I bet I wouldn't even like him."

"You would," Loki says, like it's a law of the universe. "Thor is…bright, and boisterous, and everyone loves him, even when they are displeased with him. He is impossible to ignore. And I am…not him."

"Well, I'm your friend," Steve says. "Not Thor's. That's not going to change just because I met Bucky."

Loki smirks, his expression a little easier. "And you should have a friend who can regularly rescue you from ill-conceived brawls."

"I was winning that one."

"I highly doubt that, but I suppose we must all be allowed our delusions."

It's a mild Saturday in early May and Steve is holed up in his room, studying for final exams, which is definitely one of the worst parts about high school, when Loki slips into view behind him. Steve turns his chair around, grateful for a distraction, but frowns as he takes in the flatness of Loki's expression. "What's wrong?"

Loki raises an eyebrow. "Must something be wrong for me to wish to visit you?"

"No, but you look like something's wrong. Did Thor and his friends leave you behind again?"

"Ah, no, nothing like that. They've done that rather less of late, actually, now that they've realized my seidr can be useful to them on occasion. Not that they ever remember to say so afterwards," Loki adds, bitterness creeping into his voice, "when they are all boasting of their feats and they conveniently forget that I saved their lives or made the victory possible in the first place."

Steve grimaces. "That's rough."

"At least they have mostly stopped grumbling about the presence on their adventures of someone who is not a true warrior—to my face, at any rate."

"So," Steve says. "What's wrong?"

Loki sighs. "Yesterday was my birthday."

Steve frowns. "I take it you didn't have a very good one. Did everybody forget or something?"

Loki hesitates. "Not precisely. No. Mother gave me a book on magical theory, Thor's gift was a new set of throwing knives, and Father gave me an enormous broadsword, which…I cannot use without drastically changing my fighting style. Well, he had it delivered to my chambers, anyway. He was…very busy."

"Does that happen a lot?" Steve asks.

"He does seem to be rather less busy when Thor or his accomplishments are being celebrated," Loki says, not quite tartly, and then he shakes his head. "Forgive me. I should not—it is unimportant, truly."

"I asked," Steve says. "And it kind of sounds important to you."

"Jealousy is unbecoming," Loki says, like it's automatic, and Steve gets the strong impression it's something he's been told more than once.

"That's not—what? How is it bad to be upset about something unfair?"

Loki shrugs, looking down. After a moment he says, "We Aesir live such long lives that we mark such events differently as we age, or at least that is the common practice. Young children's birthdays are celebrated every year; later, perhaps the day is marked in small ways but is truly celebrated once each decade, or once per century for adults and those nearing adulthood. I am approaching that age myself, so it is not as though I expect a regular, lavish celebration or anything of that sort. It is only…"

"Thor gets a bigger party?" Steve guesses.

"A feast of some kind, most years," Loki says, his voice flat. "It is good for our warriors' morale, you see. When he turned 750, the festivities lasted nearly a fortnight, and he was gifted with Mjolnir, a weapon of great power. So I thought…well."

"Yesterday was your 750th too," Steve says (it still feels unreal to him to measure someone's lifespan with numbers that high, but when he does the math in his head, he's pretty sure that's about equivalent to 15, so basically Steve's age).

Loki looks down again and nods. "In truth, I am not sure anyone remembered this year was anything out of the ordinary."

Steve and his mom have never had much, but she's always managed to make Christmas and his birthday special in some small way, taking extra shifts to afford an art book for him or ingredients for a cake. He's been a little jealous sometimes of the stuff other kids' parents can afford, but he's never, ever felt forgotten. In every other way, Loki's so much richer that Steve can barely comprehend it, but—

"Well," he says, "I can't throw you a feast, but I can take you to Coney Island for ice cream or something."

"Ice cream," Loki says.

"Yeah, haven't you—no, of course you haven't had ice cream, that's my fault. I don't really want to spend money on the rides right now, but just walking around is fun, and I can at least do ice cream."

"I would like that," Loki admits.

Getting to Coney Island takes a while, but it's a nice day, not hot enough yet to make the subway ride miserable. At least, Steve isn't miserable; Loki starts looking wilty almost as soon as they get into the train car, enough that Steve gets a little worried, but after a few moments of concentration, Loki produces an invisible bubble of cool air surrounding both of them. Steve is impressed and more than slightly jealous. Once they leave the train at the Coney Island station and get back out into the open air, there's a decent breeze coming off the water, and Loki lets the working go.

"How long have you been able to do that?" Steve asks.

Loki considers. "A century or so now, I suppose. Temperature control is not typically among the early skills taught to young mages, to my knowledge, but I was motivated."

"Asgard summers are pretty hot?"

Loki shrugs. "Sometimes. The heat never seems to bother anyone else overmuch, but I have long been…more sickly than others. Simply another example of a constitution ill-suited for a warrior, I suppose." His voice is doing that thing again where its deliberate lightness doesn't quite mask whatever he's trying to hide, although at least in this case Steve knows exactly what he means.

"I still get sick in the summer, usually," he says, and huffs out a laugh. "Well, I can get sick any season, it's the one thing I'm good at, but summer especially when everything's hot and muggy. Here we go, this vendor doesn't charge extra for toppings."

Loki balks again when Steve pulls out his wallet. "You needn't, truly."

"I know," Steve says. "But it's your birthday, and I want to." He buys them both double-scoop cones with chocolate sauce and hands one to Loki as they head down the boardwalk. "Careful, it'll melt and start dripping if you don't eat it fast enough. Uh, but don't eat it too fast or you'll get a headache. You just lick it."

Loki smiles sidelong at him, looking faintly amused. "I think I can manage." He licks at the ice cream once, delicately, and then his eyes widen a little and he returns to it with a lot more enthusiasm.

"I guess you like it," Steve says, grinning.

"This is good. I wonder if the cooks at home could make something similar." He catches a drip running down the side of the cone. "How is it made?"

"No idea. I bet we could look it up somewhere, though. I think it's milk, ice, and sugar, mostly."

"Mm." Loki's almost reached the cone already—maybe Asgardians just don't get ice cream headaches—and is finally slowing down. "Well, if you can find me a recipe, I will see what can be done." He neatly sidesteps a child running between them and smiles at Steve in a way that makes his heartbeat pick up. "Thank you, my friend."

Steve ducks his head. "Glad you like it." His own ice cream is starting to melt, and taking care of that keeps him occupied for a few minutes. Then Loki hops up to sit on the boardwalk railing, facing the beach and the water. Steve scrambles up next to him a lot less gracefully, but he manages, and for a little while they just watch the boats and beachgoers, with the Wonder Wheel standing sentinel overhead.

"When is your birthday?" Loki asks.

"July 4, actually. Just a couple months away now. There's always…" His lips twitch. "My mom used to say the fireworks were just for me, like the city was wishing me a happy birthday too."

"I am afraid this is another custom with which I am unfamiliar."

"Right, yeah, of course. July 4 is America's independence day, since back in—well, actually, that's not important. Everybody celebrates with fireworks, they're like colorful little explosions, and we don't have a great view but my mom started taking me up to the roof to see better." Steve laughs a little. "I think she felt bad after a while for telling me the fireworks were for me, but I'd already figured it out, and honestly I didn't mind. I'm nobody special, I know the city's not going to celebrate me, but it's still nice feeling like everyone's celebrating with me."

"Well," Loki says, "to your assertion that you are 'nobody special,' I would be inclined to point out that you are almost certainly the only living human to count a prince of Asgard as a friend. Which…focuses on me rather more than I intended."

Steve snorts. "That was pretty much luck anyway, right? You could've stumbled across anybody."

"True enough. But I met you instead, and I am glad of it. If either of us has cause to be grateful for that luck, I think it would be me." He darts a glance toward Steve and then away, studying the shoreline, and Steve is suddenly struck by how beautiful Loki is. He's noticed before, but not quite like this, with the breeze ruffling Loki's hair and the sun highlighting those fine, sharp features Steve is always itching to draw. He doesn't just want to draw Loki now, though; mostly he's wondering what it would be like to kiss him.

It's a dangerous thought for a whole bunch of reasons, so he stuffs it down and clambers back down off the railing. "Let's keep going. My butt's falling asleep."

Loki laughs but follows him. They spend the afternoon wandering between the beach and the amusements lining the boardwalk, and if Steve finds himself wanting to take Loki's hand, well, at least he keeps himself from acting on it. By the time they get back to Steve's apartment, the sun is low, his shoes are full of sand, his trousers are stiff with dried seawater from a failed attempt at outrunning the waves, and his face is sunburned, but he can't imagine why he would care.

"Thank you," Loki says again, stopping in the shadow of Steve's building. "Truly. I am indeed lucky to count you as a friend, Steve Rogers." He steps back, still smiling, and vanishes.

The next time Steve sees him, it's slightly more than two months later and he's sitting on the roof sketching the skyline when Loki pops into existence next to him. He's doing a terrible job of trying to hide a self-satisfied grin, so whatever his latest prank was, it must have gone well. Before he can ask, Loki says, "Your birthday is soon, yes?"

"Last week, actually."

"Damn. I'd hoped to find you on the day itself, but—well, nothing for it now. I wanted…" He reaches into a satchel, hesitates, and pulls out a small wooden box. "I brought you a gift. A small thing, but—I hope you like it."

Steve sets his sketchbook aside and takes the box, intrigued. The top opens on a hinge; inside, cradled in a nest of straw, is a black crystal ball about the size of Steve's two fists, with a polished wooden base. When he pulls it out, flecks of color glint across its surface wherever the sun hits it. It's pretty, but he can't think why Loki would give him a fancy paperweight, and he's not sure how to ask without sounding ungrateful.

"Put your hand on the sphere," Loki says, his voice still full of suppressed excitement, "and think of your fireworks."

Steve does. A tiny spark of light shoots up from the base of the globe and bursts under his fingers, then another and another, red and blue and gold and green, spiraling downward and fading out before exploding again, and his confusion turns to wonder as he stares at it. It's like a snow globe but it's full of little fireworks instead, fireworks that look just like the real thing in silent, miniature form. He turns it in his hand and the lights follow the motion, sinking back to and shooting out from what's now the bottom, in spirals and spiders and starbursts.

"Fireworks in a jar," Steve says. "This is incredible."

Loki grins. "It is, isn't it? I didn't make the globe, of course, I bought that, but the enchantment is mine, built from scratch."

Steve turns the globe again, marveling at the tiny little world in his hands. "I thought you didn't know what fireworks were?"

"As it happens, they are a very old invention—as Midgard marks time, anyway—so I was able to observe some myself at a celebration of some kind in China, and I replicated those. So…now you have fireworks that really are just for you."

The globe is slightly warm against his palms, and Steve closes his hands over it. "This is—way better than anything I gave you."

Loki looks at him with a crooked smile. "I suppose that is a matter of perspective."

"Okay, well, I think it's great. Thank you."

"You are most welcome," Loki says, which would sound formal and not entirely sincere coming from anyone else. "I also…wanted you to have something from Asgard, something you can keep."

Steve glances up sharply. Maybe that shouldn't sound final, but it does anyway. "Why?"

"Must I require an additional motive for a gift?"

"No, but that sounded like you have one anyway."

Loki shrugs. "Pessimism, most likely. I have no talent for seeing the future, but it has become slightly more difficult for me to find you, and in case that trend continues—well. I may be concerned for nothing. But—selfish as it may be—I would like a reason to be remembered, I suppose."

Steve straightens, frowning. "I wouldn't need a reason to remember you. And what do you mean, it's getting harder to find me?"

"Time travel is…rather more complicated than I realized when I began experimenting as a child. Thus far I have met you at appropriate points along your personal timeline. There may simply be longer gaps between visits."

That's probably underselling it, but it doesn't sound like there's anything Steve can do about it, so he sets it aside. "I've been wondering about that, actually. How come you're so much older than me but you look like you're about my age every time we meet?"

"I have wondered that myself," Loki admits. "We seem almost to be keeping pace with one another, so that every time I seek you out, we are both at proportional stages of development even though far more time has passed for me," which Steve is pretty sure is exactly what he just said except using more words. "I would like to think I am simply that good—"

"And humble, don't forget that."

Loki elbows him lightly. "Do not interrupt. I was saying I would like to think so, but I am not entirely sure even the greatest mages would be capable of such precision. I am not even doing anything particularly special, not after the first few times when I deliberately sought you out, and I rather think it was mostly luck that I succeeded at all."

Steve's eyebrows go up. "So is that your way of saying you have no idea, for once?"

Loki shrugs. "I have a theory, no more."

"Of course you do."

"I might even be convinced to share it with you, if you believe you can cease interrupting long enough for me to do so."

"I'd just like to point out that everything you say is about five times more wordy than anything I say, so interrupting you is kinda inevitable if I want to say anything," Steve says, and then raises his hands when Loki glares at him in mock severity. "No, sorry, go ahead, enlighten me."

Loki snorts. "I doubt it rises to the level of enlightenment. I simply suspect that there exists some sort of temporal anchor binding our timelines together."

"…you call that simple?"

"As a theory in relation to our situation, yes. As a theory in general, no, but it is hardly necessary to understand the particulars. You haven't come into contact with any magical artifacts, have you?"

Steve blinks. "Uh. No? Pretty sure I would've noticed, unless you mean this." He holds up the fireworks again, the globe tingling very slightly against his skin.

"Something rather more powerful, I think," Loki says. "As you say, you would have noticed. It could be something I have already encountered that is yet in your future, powerful enough for its effects to ripple outward across both our lifelines." He shrugs again. "Or perhaps it is merely luck."

"I've never been very lucky, so I doubt it," Steve says.

"Yes, well, if you were, I imagine you would've encountered Thor instead." Loki climbs to his feet and offers Steve a hand up. "How do you feel about finding some real fireworks?"

"That sounds like a terrible idea," Steve says, which of course means yes.

This story is complete on AO3, by the way; I'm just reposting it here, probably one chapter every few days.