By all accounts, 17-year-old Casil McArthur had been enjoying a perfectly successful modeling career up until last year, shooting editorials and walking runways everywhere from Singapore to Los Angeles to Toronto since age 10.

For McArthur, though, it was a different story: He’d been struggling with gender dysphoria for years, which came to a head two years ago after meeting with a spread of larger agencies to sign with in New York. “You know, my model’s name back then was Dani Rose,” McArthur said. “And I just couldn’t model as a girl anymore.”

Back home in Estes Park, Colorado, McArthur took time off to begin transitioning, though he didn’t stay away from work for long. Shortly after coming out to his friends and family, he laid it all out to his agents: “If [a girl]’s what they wanted me to be me, I wasn’t going to work for them, because I’m a man who wants to be a male model,” McArthur recalled.

Immediately accepting, they helped him sign with Soul Artist Management, a New York agency known for its hunks, and soon, McArthur was back in New York, this time much more comfortable, and hitting it out of the ballpark. The day he flew in, he went on a go-see with the photographer Collier Schorr, which led to a two-hour conversation and the start of a photo series that ended up stretching on for months. From there, he booked a presentation with Calvin Klein, plus shoots with other big names like Craig McDean. Then, he landed the big one, a 16-page spread in W's September issue shot by none other than Steven Meisel, a nonpareil spotter of talent who booked McArthur as a six-month exclusive.

“It’s been pretty fun since [December],” McArthur said with a grin.

McArthur was speaking recently about his burgeoning success when he became reflective. “But I have to relearn the business,” he continued. “It’s not difficult, but guys pose differently, and they have to do different things.” That’s true off-camera, too: “I have to learn how to give handshakes now,” he said – something that struck him in particular on his first visit to Soul’s offices, shortly after he’d started taking testosterone. He couldn’t help but feel he “didn’t compare” to the more muscular types covering the agency’s walls. “It was really difficult, but at the same time I was so happy to be out there and modeling as a male."

Now, it seems, those fears are long gone: “My goal is to one day become a supermodel,” he said. “And I don’t see how that can’t possibly happen. I think I have all of the tools to help ensure I have a long career.”

Though he's been repeatedly warned those are lofty goals – not because of his gender identity, but simply because male models have a shorter lifespan than females and few if any graduate to supermodel status – McArthur has one other ambition: he hopes to be a role model for trans teens, especially those transitioning from male to female.

“It’s important to me that I become a really good face, support and role model for the trans community,” he said. That’s evident in the way he talks openly of experiences often brushed under the rug: The difficulties of wearing a chest binder in an apartment full of male models, for example, or not being able to afford a top surgery. “It’s honestly much easier to just tell people straight up than to try and hide myself, because I am who I am, and if someone’s not going to see me as a guy, then that’s literally their problem,” he said matter-of-factly.

At the same time, though, McArthur’s trying to be a normal kid: He still lives in Estes Park, where he’s been working as a barista at places like the Stanley Hotel, which you might recognize from "The Shining." He flies out to New York often for shoots, but back home, there are his classes (he has a year of homeschooling left), his four guitars, his tight-knit crew of friends, and, most importantly to McArthur, room to experiment with cosplay, a passion immediately apparent from the characters covering both his Instagram feed and the pins on the message bag he uses to tote around his iPad, home to a store of cosplay photos he’s more than eager to show.

Modeling, McArthur laments, has put a dent in the time he can devote to it, but it’ll always hold a special meaning for him: “I got put into a community that was so different and out there and accepting and so loving,” he said of when he first started going to conventions like Star Fest (devoted to "Star Trek" and "Star Wars") and Nan Desu Kan (anime) three years ago. In fact, their acceptance, particularly when he cosplayed male characters, was a major part of what encouraged him to come out – something that previously hadn’t dawned on him could truly be a possibility.

It’s just one example of how passionate McArthur can be – a trait that seems to have captured the hearts of big names in the fashion industry and engendered close relationships like the one he has with Meisel, who encouraged him to turn up the volume on the Nirvana album he played during their shoot. “He sees me in a different light, and it’s allowed me to really be me," McArthur said of the legendary photographer.

With Schorr, too, it goes particularly deep: “I think Collier and I come from similar places, and we’re really close now. We come from different periods of the LGBT community so we learn new things from each other,” he said. “If you look at the photos, she’s telling a story: She’s documenting my transition and how we’re growing together as a team.”

She’s hardly the only legend he’s found a similarity with on set: After his first shoot with Meisel, McArthur started showing the makeup artists his cosplay, which caught the eye of one Pat McGrath, who grabbed his phone and started showing everyone else on set. “She was just like, ‘Ooh, fuck, who does your makeup?’”

McArthur told her himself, which caused McGrath to pause, look at him, and address the room: “Yeah, he’s better than me.”

Additional reporting by Karin Nelson.

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