The song is about 30 seconds long....which greatly upsets me.
Title: 天堕-序章-, Not sure how to read the first part, second I'm pretty sure means 'Prologue'
Kenn's Comment: Given that 'Prologue' is in the title, I'm really hoping this is just a teaser for a full length song that'll come out in the future. It's so freaking good! IA's voice in this one is just so well done and the PV too! It looks like it's the trailer for an upcoming game or something. Song definitely is reminiscent of something of that sort.
If a full song does come out, I'll put it up and try to link it back to this one.