Warning: Contains SPOILERS for The Kissing Booth 3.
The Kissing Booth 3 emphasizes the biggest problem with Elle (Joey King) and Lee (Joel Courtney) friendship. Netflix's rom-com franchise based on Beth Reekles' books of the same name wrapped up with the release of its third film. In it, Elle, Lee, with Noah (Jacob Elordi), and Rachel (Meganne Young) decided to make the most out of their final summer together before everybody goes to college.
Coming into The Kissing Booth 3, The Kissing Booth 2 set up the conflict between the Flynn boys regarding where Elle might go to college. She was unsure whether to go to U.C. Berkeley as she and her best friend planned, or go to Harvard so she and her boyfriend no longer have to deal with their long-distance set-up. To make matters worse, Elle was accepted into both schools, forcing her to make the decision on her own. There was an assumption that this was going to be the central plot for the threequel, but it was quickly resolved at the beginning after Elle decided to go to Boston, which made Noah happy but left his younger brother frustrated.
Lee was initially mad about it; he didn't like that Elle was breaking another friendship rule as she did when she started dating Noah. He said that he felt abandoned by his best friend. So, she tried to make up for it by promising to finish all the items on their summer bucket list. This pacified him for a bit, but with the task list too long, accomplishing all of them in a matter of months was difficult. It meant that they would have to stick very close to their schedule if they want to accomplish everything. This wasn't a problem for Lee, but things were different for Elle — who had to get a part-time job, babysit her brother, and also spend time with her boyfriend. It didn't take long before their plans fall apart, and while Elle was also partly to blame for not being more forthcoming with her struggles, the whole issue goes back to Lee and how he could be controlling.
He was so focused on Elle that he didn't even have a proper arc with Rachel. In fact, what's more odd about Lee's fixation on his best friend's future is that he didn't have the same issues with his girlfriend who's also moving across the country for college. As revealed in The Kissing Booth 3, Rachel was going to Rhode Island School of Design, and while Lee had already started planning how they will navigate the long-distance relationship, he wasn't hanging by her every move throughout the end of The Kissing Booth's trilogy. Granted that he and Elle's relationship go way farther than his romance, it's just weird that he seemingly has the urge to control his best friend more than anyone else.
Perhaps it has something to do with his rather complex relationship with Noah, feeling like he's taking away Elle. Lee talked about the supposed tug-of-war between him and his brother for her attention, lamenting that he'd always come second to Noah. Regardless of his unresolved feelings in The Kissing Booth 3, he's still exhibiting toxic behavior, and there are better ways to deal with it than emotionally manipulating Elle.