The Sunlit Garden - Finale - S1.E5

In the tune Anthy just casually played, Miki found a "glow" that he had been seeking. He has a twin sister, Kozue, who used to play a tune with a "glow". However, she does not play the piano anymore because (he thinks) of his fault. Miki wishes to protect Anthy's "glow" in her tune; however Anthy tells him that, because she is the Rose Bride, by the Rose Signet Code, she must obey the Victor of the Duel, or Utena at the moment. She even says that, if Utena told her not to play the piano anymore, she would not. Since he thinks it is his own fault that he lost Kozue's "glow" in the past, not to lose a "glow" again, Miki challenges Utena to a duel and tries to set Anthy free and protect her with his own hands