Clients love to ask sex workers, “What’s your real name?” It’s a power move. “I know you contain multitudes” is what they mean, “and I have the right to see.” They paid, after all.

The clients who asked this question of me were usually the type who had tricked themselves into believing that we had a personal relationship — a romantic one, or a sexual one they wouldn’t have to pay for had we met under different circumstances.

When clients pried, I liked turning the question back on them.

“John is my real name!” he might say, laughing at the idea that he, unlike me, would have anything to hide.

“John is my real name too,” I might say with a wink.

For the better part of a decade, I was Mistress Natalie, a professional dominatrix. A teasing sense of humor was an asset on the job.

I didn’t always act coy in that situation. Occasionally a client would ask for my real name, and I would answer honestly, telling them that my friends call me Chris. It was a powerless move. “I contain multitudes” is what I meant, “and don’t want you to think this is all I am.”

I told myself that these clients were different — young, like me, or graduate students, like me, or queer women, like me. I needed to believe they could see the me beneath the corsets, fake eyelashes and thigh-high boots.

This was always a bad reason to tell a client my real name. There was rarely a good reason. A fake name is a boundary, and some clients have no problem pushing a sex worker’s boundaries.

I still receive emails from a female client who began pursuing me obsessively after she learned my first name.

“Dear Chris: I’m going to build a house someday, and I hope you’ll live in it with me.”

“Dear Chris: You’re the love of my life.”

“Dear Mistress Natalie: When I first came to you, I was nervous and you made me feel comfortable. As I’ve had time to reflect, I realize that I overstepped my boundaries with you.”

I try to ignore these messages, but it’s hard. I’m afraid of her. My girlfriend was afraid of her, too. The client sent gifts from my Amazon Wish List, which piled up on our doorstep while I was away.

“Don’t worry, baby,” I said to my girlfriend. “She doesn’t know my last name. She doesn’t know how to find us.” But I didn’t know for sure.

After that girlfriend and I broke up, I was alone in my fear, which came as a relief.

Nearly a decade ago, in a hotel room in a southern city, I met a client who was another graduate student. His name really was John, and John’s Ph.D. would be in computer science. Mine would be in the humanities. This explains why he had money to hire a dominatrix and I had so little that I needed to play one on the side.

When John walked into my room, I thought he was cute. When he told me all he wanted to do was kiss my leather boots, I thought, “Easy money.” When he told me he had a girlfriend, I wondered why he couldn’t kiss her boots for free. (Our culture really does a number on men who are interested in sexual submission.)

“What’s your real name?” John asked after the session.

I didn’t give him the name my friends call me, Chris, but the name my parents gave me, Christina. I told him I was a Ph.D. student like him, studying English. I contain multitudes!

With a little research, he was then able to find my last name.

When I was back home, he texted: “So, Doctor, what happens if I start developing feelings for you and want to see you on a different level?”

I ignored him.

A week later, using my full name, he made it known that he had read my academic articles, something I couldn’t even convince my then girlfriend to do.

My cheeks burned as I read the text, knowing it was my own ego that had lured me into dangerous territory. I told John to call me “Mistress Natalie” but didn’t block his number.

That Christmas, he texted to say that he was in Orange County visiting his parents. When I saw his number flash on my phone, I remembered that he knew my real name and didn’t answer. He left angry voice mails, ranting about how I had stoked his obsession and left him hanging.

“Christina,” he pleaded, “don’t ruin my Christmas.”

I had been working for a few years by the time I met the woman who still sends me the inappropriate emails, but I could have counted the number of female clients I had seen on one hand. I was fine with that. Female clients were more complicated. I had a harder time separating professional from personal. I had a harder time saying “no” when they asked for my real name.

In B.D.S.M. practice, “after care” is important, so I offered hugs to every client at the end of a session. It seemed like the least I could do. With that woman, I let the hugs linger. She could count on four, five cycles of breath before I would pull away. She would take more if I let her.

After our sessions, she would text me to say that the hug was her favorite part.

The last time I saw her, she had shown up to meet me in a hotel lobby — shoeless and strung out, with no money for the session she had booked — in a city where the police were rumored to be doing prostitution stings in high-end hotels.

Professional B.D.S.M. exists in a gray area of the law: It’s not prostitution, the acceptance of money for sex, but only because sex is hard to define. I didn’t think cops running a sting operation were likely to delve into the ambiguities, and I didn’t need an erratic client getting me arrested. I had just defended my dissertation and was about to enter the academic job market. So I gave her cash to get her car out of the hotel parking lot where she had slept and vowed to never see her again.

At the time, I belonged to a sex worker self-defense collective. We spent hours each week drilling strategies to deflect touch. We practiced maneuvers meant to forcibly remove hands from the small of our backs, to break grips on our wrists. We talked about boundaries and how to set them.

It took the collective an hour to persuade me to stop engaging with this woman. After that morning in the hotel lobby, she had threatened to hurt herself if I didn’t see her again, but I had sworn that I wouldn’t.

“I can no longer have contact with you,” I wrote as my support system looked on. “I wish you the best, but you have persisted in contacting me against my wishes.”

I made a friend press “send.” I turned off my phone for 12 hours, afraid of her response. All I could think was: She knows my real name.

Either way, I still hold my breath when I open my old work inbox, bracing myself for love declarations or worse — that she could find out where I live, show up at my door and ask for another chance at a love she never had.

Fear is a weapon wielded by those who want to keep others silent, and the stigma against sex work makes it easy to scare or blackmail us. So finally, a few years ago, I came out as a sex worker. My name is no longer a secret to anyone. I didn’t come out because I am fearless. I came out because I am sometimes still afraid, and I know I’m not alone.

In general, though, I was rarely afraid of my clients, the fumbling fathers who showed me iPhone photographs of their children and dogs, the sweet-if-clueless guys who asked for my advice on their dating profiles. Even John — the Ph.D. student who used my real name — called a year later when he was again home for the holidays to apologize. “I’m a fool when it comes to feelings,” he wrote. “That’s why I acted the way I did.”

He said he was in therapy, and I agreed to see him again. He sounded sorry, I needed the money, and it was Christmas, after all.

Chris Belcher, an assistant professor of writing at the University of Southern California, is the author of the memoir, “Pretty Baby.”

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