This was the second song featured as a PV for the game.
アンティフォナの聖歌姫 ~天使の楽譜 Op.A
Antiphona no Seikahime ~Tenshi no Gakufu~ OP. A
The Hymn Princess of Antiphona ~Angel’s Score~ Op. A
For those curious to listen to the rest of the soundtrack, Zynux of Youtube has a playlist.
I think this song is particularly sweet, so I figured I would sit down and do a quick and easy translation for it.