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.
Of course I won't. 
Nobody would believe me, anyway.
Natürlich werde ich das nicht.
Mir würde sowieso keiner glauben.
No lo haré. Nadie me 
creería de todos modos.
No diré nada. De hecho, dudo 
que alguien me creyese.
Je n’en parlerai pas.
É claro que não vou contar.
Ninguém acreditaria mesmo.