If these two people don’t get together, I will die.
Romance has always been a part of science fiction and fantasy. Sometimes it’s a love story for the ages. Sometimes it’s the hero and a sexy lamp. I’ll admit that one of my stronger memories of getting into classic SF is developing the ability to spot a possible romance scene within the first three sentences so I could skip the subsequent pages and get on with the story—I didn’t care about the lady with no personality who was the hero’s reward for saving the day, and I definitely didn’t see myself in her.
But then I started to find SF and fantasy romances that actually worked for me. Part of that was just finding the right books. Part of it was the rise of queer romances in mainstream SFF: a sudden glorious flood of queer people who are allowed to be happy and go off into the sunset without dying tragically. Queer or straight, I started to find characters I cared desperately about. Characters who, it was clear, wouldn’t be happy unless they acknowledged this other person who was obviously part of their soul in a way no two people had ever been before in the history of literature. (This happened multiple times.)