'Gossip Girl' 's Jason Gotay on His Sexuality and Body Image — and Why He Once Felt Like an 'Imposter'

On the first season of HBO Max's Gossip Girl reboot, Jason Gotay walked through the halls of Constance Billard exuding confidence — a quality he once lacked in his younger years.

The actor, who played Rafa Caparros — a hot teacher who became entangled with one of the school's male students — tells PEOPLE his upbringing was a bit different from those of the Upper East Siders at the preppy New York City private school.

As the singer readies for his new autobiographical Off-Broadway show, titled Where You'll Find Me, he says that growing up in Dyker Heights, Brooklyn, he constantly asked himself, "Where do I exist?"

"If I'm not this conservative straight guy, but I'm not this really out proud gay kid," he continues, "who the f— am I?"

Gotay, 33, actually wears many hats: Broadway actor, television heartthrob and new husband to actor Michael Hartung, among others. In his early high school days, however, he was the "fat kid," he says.

"It started small, but then it spiraled out of control. And I was never looked at as desirable ever. Maybe people would call me cute or sweet, but I was never looked at as attractive or handsome," he shares.

He was also dealing with another side of him. "Growing up, I loved playing dress-up with [my sister] Jill, and I was doing community theater, and I was very flamboyant," he says. "I was very feminine, so I knew I was different."

Though Gotay slimmed down before heading off to Emerson College in Boston, there was something else weighing him down. He had not yet identified as gay.

"It was, of course, an acting assignment," he says, that made him realize it was time to address his sexuality head-on. When asked to answer a series of questions, Gotay had to identify what he was most afraid of.

"I wrote down that my greatest fear is giving into the temptation that has been eating away at me my entire life. I looked at it, and immediately I knew that I had confessed something that I had never put to words before," he tells PEOPLE of the moment he concluded it was time to come out. "I read it over and over, and I wanted to tear the page up and rip it up. But it was too late; I'd already said it."

The Bring It On: The Musical star — who would eventually graduate from Marymount Manhattan College — went on to tell his sister Jillian, brother Dan and mother Marla ("in that order," he notes, "and all three of them were just, I mean… incredible").

Gotay never had the conversation with his father, who drifted from their family when the Broadway performer was in his teens. "That sort of closure never really happened … [but] it doesn't really feel like something that I need to do before I die," he says candidly. "I don't feel like my family's incomplete in any way."

Being cast in Gossip Girl, Gotay says, brought up a slew of emotions — ones he will explore in Where You'll Find Me, a show that pays tribute to the influential female figures in his life and how they made him stronger. "I feel very deeply," he admits.

"What that show brought up for me, more than my own homophobia from my childhood and that shame, was a lot of stuff about my body," he explains.

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"I kept feeling that imposter syndrome, and I had to have this moment — and I think it came really around Gossip Girl — where I have to start seeing myself the way that other people see me. Because I can get the part, and I can get the validation, but if I don't start believing that I am good enough, I'm never gonna get past that wall. Because that 12-year-old fat kid, he follows me everywhere."

Where You'll Find Me plays Off-Broadway's Minetta Lane Theatre Friday through Sunday.