The "elite student in music room 2" turns out to be Haruki's delinquent classmate, Kazusa Touma.  With his characteristic pushiness, he tries to get her to join the light music club.  But his pushiness backfires, and only makes her more annoyed.  Setsuna gets irritated... no, involved, and approaches Kazusa secretly.
Sorry to keep you for so long.
Entschuldige, dass ich dich 
so lange aufgehalten hab.
Perdona por quitarte tanto tiempo.
Perdona por haberte robado tanto tiempo.
Excuse-moi de t’avoir 
retenue aussi longtemps.
Desculpe a demora.