Aria has been dealing with Sonata's stupidity for years, and she's finally had enough, resulting in a argument, but what follows is something Aria would've never actually wanted.
Everyone is at the same party, but they all have different reasons to be there. Each chapter focuses on a new set of people at the same party. Same story, just different view points.
After making peace with the Dazzlings, Sunset decides to spend time with them individually. With Adagio and Sonata out of the way, she moves on to Aria, but what blooms from this is something neither of them ever expected.