Sex with someone new and when should it happen has always been a question.

Single people are often left wondering when they should have sex with a new partner for the first time, fearing sleeping together too soon will brand them as a one-night stand but waiting too long could make the other person lose interest.

Meet Tinx, the TikTok influencer who has set out to solve for this predicament in her new book, “The Shift: Change Your Perspective, Not Yourself.” She hopes her “box theory” and other dating advice can help “rebrand” dating from “just a means to an end” to “an era of self-discovery.”

TINXWhile the book’s target audience is women and the dating tips offered are geared toward women who date men (Tinx writes in the book that she is “staying in my extremely straight lane and writing what I know”), much of the advice remains helpful regardless of gender identity or sexual orientation.

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“My main message comes down to self-worth and prioritizing your own happiness, so if that’s something you think you’d like more of in your life, you are welcome here,” she writes.

In short, Tinx advises those dating around to “act how you want in the moment: If you feel like sleeping with someone, you should sleep with them. If you feel like you want to wait, then wait, but you shouldn’t withhold (sex) to try and manipulate your way to dating someone.”

Who is Tinx?
Born Christina Najjar, the 32-year-old influencer known online as Tinx boasts 1.5 million TikTok followers. The majority of her videos are shot casually, lying in bed or standing in her kitchen, holding a tiny lavalier microphone as she shares personal anecdotes and life advice.

Some viewers online have likened her a virtual “big sister,” offering advice on love and life. Tinx views that role as “a massive privilege.”

“I feel so lucky that people trust me with their problems,” she tells USA TODAY. “I feel so lucky every day that I get to connect with these amazing women and girls who trust me enough to ask me these questions.”

What is box theory?
Tinx first shared her “box theory” on social media in 2021, based on a series of “misadventures” and time spent “chasing male validation” in her 20s.

As she describes it, the theory is that “when a guy meets a girl in a romantic setting − so like a dating app date or a blind date or something − he will put her into one of three boxes: He wants to date her, he wants to sleep with her or he wants nothing to do with her.”

“The Shift” by Tinx © Courtesy Simon & Schuster “The Shift” by Tinx
She adds: “If he wants to date you, he’s going to want to date you no matter how you act, no matter what you say. And vice-versa: If he just wants to hook up with you, you can try your hardest and try to manipulate your way into the date box, but you just can’t.”

While it might seem overly simplistic to some, Tinx views box theory as a “freeing and empowering” concept.

“You shouldn’t try to manipulate someone into wanting to date you,” she says. “You shouldn’t have to, because everyone deserves someone who is interested in them and obsessed with them. That’s available to everyone if you just don’t settle for less.”

What is reverse box theory?
While box theory is designed to help people take back power in dating and identify what they want from a relationship, reverse box theory is meant to rein the hopeless romantics back in.

“A lot of the time, women will prematurely put men in the date box,” Tinx says. “A girl will see a guy online on a dating app and think, ‘Oh my god, this guy is going to be my husband.’ … The truth is you know very little about him. You’ve just constructed this idea of someone in your head. It’s very important to wait to see how someone makes you feel and wait to see if they’re worthy of going in the date box.”

It all comes back to worth. Tinx hopes her book will help readers navigate the world of dating to find someone worthy of themselves, but also to get in touch with themselves and become “the main character of your life.”

“Dating should be fun,” she says. “It should be a fun era of exploration. A date isn’t a failure if you don’t have a second date. A date is only a failure if you don’t learn anything about yourself.”

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More: How soon is too soon to have sex when dating someone new?

This article originally appeared on USA TODAY: When should you have sex with someone new? Consider ‘box theory’ before deciding.