the rom is part of the character dev rather than the plot?

Like the plot isn't about the ML and FL's romance, but about something else, and their rom develops kinda naturally on the side of the plot... err... or maybe they're already in a relationship when the drama starts, like they're already married, but the plot is not about their marriage crashing down and being saved or whatever.

Maybe:

• Story of minglan
• First Half of My Life
• The Red Sleeve
• One liter of Tears 
• Bridal Mask / Gaksital
• Reset
• Recipe For Farewell
• A Thousand Days Promise
• Stepmother and Daughter Blues