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.
It was all Ogiso's idea.
Das war alles Ogisos Idee.
Todo es cosa de Ogiso.
Todo es cosa de Ogiso.
c’est une idée d’Ogiso !
Foi tudo coisa da Ogiso.