Equestria was attacked by demons after a crack to Tartarus opened. The races of the world gathered together to push back the tide of demons so the Elements of Harmony could get close enough to close the crack. Everyone played their part and the day was won, but not without loss.
The six mares of the Elements of Harmony now must say good-bye to a dear friend that wasn't even of their world to begin with. His last request is to simply hear them sing a song before he passes on.
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One-Shotober Story#6 10/6/2013
Thanks to Mr101 and Timps for pre-reading