The first time Maine Mendoza met RJ Faulkerson Jr., she was interning in New York. He was sweet and a little shy. She was charmed.
Later, she met him again but as Alden Richards rocking on a concert stage in a sea of screaming fans. He was suave and charming. She was stunned.
This is the Rock Band-ish/Serendipity-ish AU that nobody asked for.