Haruki is entranced by Setsuna's singing on the rooftop, and plots to get her to join the Light Music Club no matter what.  But she hates standing out, so convincing her is incredibly difficult.  Meanwhile, the club has an even bigger problem.  The elite student from Music Room 2 he was trying to persuade to join his club as the keyboard player isn't a member of the Music Class, it's a mysterious person whose class and identity are a total unknown.
I could sing all day long!
Ich könnte den ganzen Tag singen!
¡Podría cantar todo el día!
¡Podría estar cantando todo el día!
Je pourrais chanter 
toute une journée sans me lasser !
Poderia cantar todos os dias!