I've always found their dynamic fascinating because it starts from pure ideological opposition. Like, Ronnie views the world through this rigid, survival-of-the-fittest lens, while Lincoln is all about empathy and second chances. Early fics often have them forced together—maybe stranded after a mission gone wrong or stuck in a safe house. The tension isn't just 'will they or won't they kiss'; it's 'can they even stand to be in the same room without trying to kill each other?' That mutual disgust slowly curdling into a grudging respect is the foundation. Then you get the accidental physical contact, the shared glance when another character says something that hits them both, and suddenly they're arguing not to win, but to get a reaction from the other.
A lot of writers build the romantic payoff around Ronnie's vulnerability. Seeing this hardened, cynical person let their guard down just for a moment in front of Lincoln, maybe when they're injured or exhausted, hits so hard. Lincoln’s the only one who wouldn't exploit that weakness, which makes Ronnie's trust feel earned. The best stories make you believe that their love is a conscious, difficult choice, not just a plot device. It feels like they're building something entirely new together, brick by painful brick.