Zareen Jaffery had a hunch.

When the executive editor at Simon & Schuster Books for Young Readers was reviewing the final manuscript of “To All the Boys I’ve Loved Before” with its author, Jenny Han, she could already picture the movie.

“I can totally see this on TV,” Jaffery recalled telling Han.

That prediction became a reality last summer when Netflix released Han’s New York Times bestselling book as a sweet and heartfelt romantic comedy starring Lana Condor as Lara Jean Song Covey and Noah Centineo as Peter Kavinsky. Audiences fell for Han’s characters over and over again: The film became one of Netflix’s most rewatched original movies in 2018. Thankfully, Han wrote three books about Lara Jean. The first novel published in 2014, followed by “P.S. I Still Love You” and “Always and Forever, Lara Jean.” The second book will serve as a blueprint for the “To All the Boys I’ve Loved Before” movie sequel, which is now in production.

But years before audiences would be able to swoon over Lara Jean and Peter onscreen, Han was still fleshing out the details of their story, which she started working on in 2010. The idea came from a teenage memory of her own: In high school, Han wrote love letters to boys she was trying to get over and stored them in a hatbox. Lara Jean does the same thing, but when her little sister, Kitty, secretly mails the letters, her life changes in unexpected ways.

During the writing and editing process, Jaffery and Han discussed a source of inspiration for the author: Korean dramas. Contracts, for example, are a popular trope in K-dramas, and Han incorporated them into the trilogy. When Lara Jean and Peter pretend to date in the first book, they establish ground rules by making a contract. It includes this promise: “Under no circumstances can either of us tell anyone the truth.” The teens believe their fake relationship is a clever way to distract Peter’s ex-girlfriend, Genevieve, and one of Lara Jean’s past love interests, Josh.

 “To All the Boys I’ve Loved Before” stars Lana Condor, left, as Lara Jean Song Covey and Noah Centineo as Peter Kavinsky. Anna Cathcart (center) plays Kitty, Lara Jean’s younger sister. (Awesomeness Films/Netflix)
“To All the Boys I’ve Loved Before” stars Lana Condor, left, as Lara Jean Song Covey and Noah Centineo as Peter Kavinsky. Anna Cathcart (center) plays Kitty, Lara Jean’s younger sister. (Awesomeness Films/Netflix)

“Those are always my favorite kinds of Korean dramas,” Han told The Lily. Characters “are set on a path, and [they think] that they understand how the story’s going to go.” The audience knows the characters are only fooling themselves. Somewhere along the line, the story is upended, much like when Lara Jean and Peter realize they have real feelings for each other.

In Han’s story, the contract represents something else, too: consent. Lara Jean knows who she is and what she is and isn’t ready for. More importantly, she’s mature enough to have that discussion with her — albeit fake — partner. When she insists on including “no kissing” in the contract, Peter pushes back: “Are people really going to buy it if we never touch each other in public?”

Lara Jean remains steadfast. “I don’t think relationships are just about physicality,” she says before agreeing to occasionally allow Peter to put his hand in her back jean pocket. “There are other ways to show you care about someone, not just using your lips.”

Consent is a running theme throughout Han’s trilogy. In “P.S. I Still Love You,” Lara Jean and Peter write a new contract. This time, they’re a real couple, and Lara Jean is thinking about sex: Peter isn’t a virgin, and her older sister and best friend have both had sex. But ultimately, Lara Jean sets her own boundaries, and Peter respects them.

“I wanted to celebrate that there’s all different kinds of ways to come of age,” Han said. “It’s about finding your own time and what makes you feel comfortable and good.”

“A thing that a lot of young people fall into is feeling like you’re supposed to be on some kind of clock,” she added. “You see people around you doing stuff, and you’re like, ‘Should I be doing the same thing? I’m starting to feel behind.’”

In her trilogy, Han emphasizes that growing up isn’t attached to a rigid schedule that everyone has to abide by. It’s something Condor, the actor who plays Lara Jean, respects about the author.

“Jenny is being such a wonderful role model to so many people in the world,” Condor said.

“She’s reminding them, ‘Hey, slow down. Your body, your heart and your mind is yours.’”

Han’s books fall in the “young adult” category, but the themes are universal. Everyone can relate to feeling “behind” in life and being uncomfortable with change, as Lara Jean is when her older sister, Margot, first goes to college. Later, she deals with her father entering a new relationship years after her mother’s death and contemplates what will happen when she goes to college herself.

“I never like to think about my books in terms of lessons, but if there was a lesson, it would be that family will continue to change over the course of your life. That’s just a part of [life] that I don’t think ever gets easier,” Han said. “Parents might get divorced. Maybe you’ll get divorced. Parents will pass away at some point, and then you’ll have new family. … Change can feel traumatic, but there are other ways to look at it and be able to still feel secure with all the change.”

Han grew up in the ’80s and ’90s and lived in Richmond, Va., with her parents and younger sister. Her pastimes mirrored some of Lara Jean’s — baking, shopping and writing — and a list of her favorite TV shows will make some Gen Xers and millennials feel warmly nostalgic: She watched “My So-Called Life,” “A Different World,” “ER” and anything that aired on the WB, like “Buffy the Vampire Slayer,” and later, “Felicity.” (The now-defunct TV network lives on through the CW.)

After graduating from the University of North Carolina at Chapel Hill, she moved to New York, got her master of fine arts at the New School and began working as a children’s librarian at the Calhoun School. Han published her first book, “Shug,” in 2006. She went on to pen several more books, including “The Summer I Turned Pretty” series.

When Han creates, she has a clear vision for the final product. She wanted a photo of an Asian American girl for the “To All the Boys I’ve Loved Before” series covers, particularly since the main character and her sisters are Korean-American. (Han’s parents have read her books in English and Korean.)

When it came time to turn the book into a film, she pushed for the same representation onscreen. In an op-ed for the New York Times last year, Han wrote that initial interest in buying the rights to the book “died as soon as I made it clear the lead had to be Asian American.”

“I ended up deciding to work with the only production company that agreed the main character would be played by an Asian actress,” Han continued in the Times. Han was involved throughout the filmmaking process, helping to determine Lara Jean’s style and what her bedroom might look like.

Before Condor ever auditioned for the role of Lara Jean, she and Han were already aware of each other through social media. A few months before the premiere of “X-Men: Apocalypse” in 2016, Han had shared a post on Instagram fangirling over Condor, who played Jubilee in the film. Condor remembered the moment well: “It is just a testament to how supportive Jenny is. ... She is building up and celebrating women that she doesn’t even know. We need to do more of that.”

Now, the author and actor have a genuine friendship. They communicate in some way almost every day, Condor said, and they still share snaps of each other on Instagram. Lately, their social media accounts show that they’ve been back on set filming the sequel, which will also star musician Jordan Fisher, Ross Butler of “Riverdale” and “13 Reasons Why” fame, and Sarayu Blue from NBC’s “I Feel Bad.”

Through her writing, Han created a world in which readers see themselves. As Jaffery put it, “When you read her books, it feels like a real place that you can go visit.”

“I felt such a familiarity with these characters and her perspective,” Jaffery, who is Pakistani-American, said. “I know so many people from my community who read these books and were like, ‘Oh my gosh, Lara Jean is me. I’m someone who is really close to their family, and I don’t really want to get out of my comfort zone.’ ... People connected to the emotional core of this character.”

Of course, it’s not all about Lara Jean. Each character in Han’s book gets special attention. Her pages offer readers examples of what respect looks like in romantic relationships, friendships and families. Much like in real life, her characters are layered and at times flawed.

Han also expressed interest in writing screenplays, meaning she could contribute more positive examples to the romantic comedy genre.

She’s already succeeded once. In the movie version of “To All the Boys I’ve Loved Before,” Lara Jean “does not change herself in order to be in a relationship with Peter,” Han said.

“From the beginning to the end, she grows, but that doesn’t mean that her core self changes,” she added.

“The rom-coms that I like best honor that kind of relationship. They both get to be a more self-actualized version of who they are.”

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