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.
but whoever was playing that piano.
aber eben die Person, 
die das Klavier spielte.
pero quien tocaba el piano...
pero esa forma de tocar el piano...
qui jouais du piano…
mas quem estava tocando aquele piano.