Everyday feels a little less than the one before.
I know I’m dying
Any pony can tell that I have been for a while

Princess Dawning Dusk is dying. Every day she can feel herself become a little weaker and is haunted by visions from the future of her friends becoming evil and knows there is nothing she can do about it, until Shadow comes.
Shadow makes promises, ones that could let Dawn gain the powers she desires to be able to save her friends and not die herself.
But then Dawn finds herself doing things she would never have done before. Treating her friends and subjects cruelly and losing bits of her memory while Shadow continues to whisper promises into her ears as she feels she is fading away…