Editor's note: This tour of small businesses across the country highlights the imagination, diversity, and resilience of American enterprise.

Caitlin Johnstone is aghast at her early choice of Pokémon eye shadows.

"I was terrible at naming things seven years ago," says Johnstone, who has had to consult her records to recall offerings in the debut collection from her company, Shiro Cosmetics. "I randomly have Vulpix in there. But Vulpix isn't important. And I straight-up named one Acid because I wanted something bright green. But Acid's not even a character." (For non- Pokémon enthusiasts, Acid is a move in the game.)

"I've got one called Zubat. But no one likes Zubat," says Johnstone. "Boy, this is all over the place. I got a lot better at makeup."

Seven years after launching Shiro, a Portland, Oregon, brand that targets nerdy girls, Johnstone is indeed better at makeup. Shiro remains a niche business; its founder wants to keep it small. But the company, which she expected "might make me $20 someday," has revenues of $360,000 and comfortably supports Johnson and three employees.

Portland is at least as accommodating of geeks and nerds as it is of hipsters. The city boasts its own Quidditch league, a science-fiction live theater, a Retro Gaming Expo, and the Geek Council--an umbrella group for businesses and organizations that cater to fan-folk. It is the perfect home for Shiro, whose tagline is "making nerds sparkly since 2010!" "Shiro" is the Japanese word for "castle." It is also the name of a Pokémon trainer, who is even less important than Vulpix.

Shiro's sparkly, mineral-based products (mostly eye shadows, but also lip glosses, nail polish, and contours) target people who dress up as characters from movies, comics, or video games. They also appeal to those who just like stuff inspired by pop culture. Such customers get Johnstone's offbeat sense of humor. For example, her decision to base the annual Valentine's Day product release on an obscure Japanese anime series about ice skating, with colors like Pork Cutlet Bowl Fatale. One eye shadow collection grew out of puns about trees. Grow Home Douglas, You're Trunk is the name of a deep-green-tinted-mustardy-gold offering.

For a collection tied to the PC game Portal, Johnstone concocted colors based on insults hurled by a sarcastic robot named GLaDOS, including a "morose navy blue" called You Are Adopted. "In a lot of cases, the series that we like are kind of downers or violent," says Johnstone. "If you go in not knowing the source, you might say, 'That is a strange thing to say about eye shadow.'"

Laurel Connoyer, who lives in Seattle, has been buying Shiro's products for five years. Her personal favorite is the set of eye shadows based on The Hobbit, a book her father read to her as a child. "They do a really incredible job interpreting the themes--books I've read or TV shows I've watched and really enjoyed," says Connoyer. "There is something so interesting at seeing how a really creative person takes those themes and colors and turns them into something so different and fantastic."

A timely fracture.

Growing up, Johnstone split her time between the ranch and the track. Her father is Parker Johnstone, a racecar driver in the '80s and '90s and then a color announcer for Indy coverage on ABC and ESPN. "Our entire family would travel around with him to his races," says Johnstone. "It was a world of adults who were very, very passionate about what they did and very, very good at what they did."

When she wasn't on the track Johnstone was tending poultry and horses on her family's central Oregon ranch. Living 20 miles from the nearest town, "I was incredibly into reading. You could not find me without a Redwall book in my hand," she says. She also played Pokémon maniacally. "I was in the middle of nowhere," says Johnstone. "I loved having a handheld game that took me to a whole other world."

At 18, Johnstone enrolled at Willamette University, in Salem, Oregon, where she studied math and science. She also had a baby. To make money she freelanced: designing websites and writing SEO articles. To make it all work she lived at home.

Then one day in her sophomore year, Johnstone broke her arm snowboarding. ("They were going to give me a plate and a couple of screws. But they wouldn't give me a laser so I opted out, " she says of her treatment after the accident.) Unable to lift her son, she temporarily ceded childcare to her parents and mulled using the unexpected downtime to start a side business. She wanted something low cost she could do from home, and landed on makeup. "At the time there were a few indie businesses that sold cosmetics, but they did not cater to nerdy interests," says Johnstone. "I thought by taking inspiration from pop culture, I could get people very excited."

Johnstone funded the company with money from her son's father, whom she says had neglected to reimburse her for medical costs from the birth. "One day he comes up to the gate, and he has a check for $800," she says. "I started the company with it."

Startup costs were minimal. After studying DIY beauty blogs Johnstone ordered mineral-based pigments from a business called TKB Trading, in Oakland, California. "The great thing about mineral makeup is you are not going to mess it up in a way that is dangerous to anyone," says Johnstone. "You don't have to worry, 'oh boy, I hope this doesn't burn anyone's eyelids.'"

She also bought from eBay a gram scale and a mineral blender so tiny it produced just one ounce of product at a time. "At one point my dad found my stash of colored powders and the scale and plastic bags. He was really concerned," says Johnstone. "I told him it was just cosmetics. Really. Look. Sparkly."

As she experimented with the pigments--blending them with carnauba wax so they'd adhere better to the eyelid--Johnstone considered the theme of her debut collection. "The first thing I thought of," she says, "was Pokémon."

Wizards, warriors, and witticisms.

There are 151 creatures in the first generation of Pokémon. Johnstone knew she needed colors representing the iconic ones. Mimicking as closely as possible the hues of their skins, she whipped up a blue-green for Bulbasaur, a red-orange for Charmander, a light blue for Squirtle, and a yellow for Pikachu. She created a gray shadow for the criminal organization Team Rocket.

Johnstone launched the products on Etsy, pricing them from $1 for a sample bag to $6 for a full-size jar. She made a sale on the first day. Over the next months, while her arm healed, volume grew. Her next collection was based on the game Legends of Zelda. She hired artists to create character-based labels for each product.

Soon after, "we were doing a high-enough volume that I was paying hundreds of dollars a month in Etsy fees," says Johnstone. "I started looking for other options."

By that time Shiro was wearing out its welcome in the family home. "One time my younger brother came back from school looking like he was about to cry. The other kids had been making fun of him because there was glitter all over his clothes," says Johnstone. "Another time my dad opened up his iPad case and it was covered in glitter." Her father offered to help her find an affordable office-and-warehouse space.

Ensconced in the new digs, Johnstone in 2012 dropped out of school to devote herself full-time to Shiro. Around that time Lauren Underwood came on as shop manager and Johnstone's business partner. A fellow video game fan and an aficionado of all things Beauty and the Beast, Underwood is responsible for many of the worst puns among Shiro's product names.

In recent years Shiro has riffed more broadly off the world of popular culture, from The Hobbit to Harry Potter. To avoid running afoul of trademarks, Johnstone and Underwood come at these properties obliquely. For example, their Earth's Mightiest Heroes collection eschews the word "Avengers." Instead of Hulk and Thor, the colors bear names like Enormous Green Rage Monster and He Loves His Hammer. (One eye shadow is called I Understood That Reference.) Among Shiro's most popular collections is Seven Kingdoms, a Game of Thrones tribute that includes colors like Master of Whispers and You Know Nothing. The jars are illustrated with fan art, further avoiding infringement.

"They are all inspired-by names. No one seems to have a problem with it," says Johnstone, who re-released her Pokémon products with vaguer names when, after a year in business, it occurred to her that she might get into trouble.

New products are so easy to create--just change up the combination of pigments--that Johnstone can knock out something on the basis of a joke. A friend suggested she make an eye shadow called Nic Cage Raking Leaves on a Brisk October Afternoon, which Johnstone promptly did. (It's deep brown with golden-red sparkles.) She followed that with Cages Through the Ages lip glosses, featuring tube art of the actor dressed as a caveman, for example, or Botticelli's Venus. "We sold a lot of that," says Johnstone. "Everyone wants products about Nicolas Cage."

Fear of Facebook.

Johnstone sells occasionally at craft fairs and friends' brick-and-mortar stores. But Shiro is primarily a direct-sales business operating from a website built by Johnstone. Despite the speed at which Shiro can make product, the site has occasionally been so overwhelmed by orders--for example, after the release of the Potter tribute Marauders, Mugwumps, and Muggles--that Johnstone has had to temporarily close it down.

She attributes most of the demand to clever product-naming. But she isn't entirely sure how word about the company spreads. Johnstone has never advertised and does just a smidgeon of social media. "I am actually terrified of Facebook," she says. "The massive public aspect of it really intimidates me."

The word doesn't have to spread too far. True to Portland's artisanal ethos, Johnstone isn't trying to grow a global brand. Corporate, after all, is the antithesis of nerdy. "You would think I'd be really ambitious," says Johnstone. "But I don't see the need to push much further. Two years ago I bought a house. I have a kid, a cat, a dog, and a boyfriend. My life is so good."