Person A works as a musician. So does Person B. Person B quickly rose to the top, becoming a national star. Person A just does small gigs at bars and pubs, weddings and such. 

One time, Person B has a performance in their hometown. However, one of their essential band members hurt themselves badly and can't perform. Their manager arranges for Person A, without knowing their history, to step in. Person A and B get talking and old wounds heal. They start catching feelings for each other again, and one thing leads to another.

Possible subplot: Person A and B used to date or like each other in high school. They broke up after Person B fell in love with someone else.