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.
That was when I was a kid!
Die Abmachung galt als Kind!
¡Eso fue cuando era niña!
¡Eso es de cuando era una niña!
Ça, c’était quand 
j’étais gamine !
Foi quando eu era criança!