Have you ever heard the phrase "tension on every page"?
It is where something is askew at every moment. There may not be mayhem, but things just don't sit right...like a teetering tower. You never know when or how it will come crashing down, or if all will be right in the end. It's unstable and uncertain.
Romance is something you will often find in literature. Not just in the Romance genre but in any of them. Relationships - romantic and otherwise - will always be important in fiction. "Romance" doesn't have to mean an epic love story with feet-sweeper-offers. It can be the simplest bond between two people. Even between one person and a place or moment.
Romance is not fluff. Without tension, it's stale and irritable.
They meet, they flirt, they kiss, they hubba-hubba, and they have a jolly good happily ever after. The End.
I would throw eggs at that The End.
In some cases, romantic elements can serve as an escape from other issues that a character is facing. It is the embodiment of an ideal, an escape and a hope for a better future. That doesn't mean that it should come easily.
I'll give you an example: Two characters (whichever gender) and The Kiss.
Not the act of the kiss itself but the build-up or even the "non-kiss," the awareness of an act not taken place or a reluctance in a character to make it so.
The best way to describe this is if one of the characters has poison lips.
This could be literal, a character with a deadly venom that makes it so that they can never be kissed. Both characters yearning for what's missing between them and their desire which fills the space.
It can also be a metaphor. A hesitancy in one or both characters. The acknowledgement of uncertainty and vulnerability, struggling against a need.
The Kiss is not just the locking of the lips. It is the brush of any moment in your story that keeps the tower teetering. Don't let it rest until you reach The End.