The Elements of Harmony. A universal force of good that purifies everything it touches, defending for all eternity the glory of candyland Equestria. But still, things aren't as they seem, as they almost always are. There are side effects to great power, and these effects take the Harmony right out of the equation.

Spike is a good assistant. Better since the Elements were used, in fact, but at a price. He is but a shade of his former self. While a far cry from a different person altogether, Spike has become little other than an assistant, not even pursuing his interests during break time, or when there's nothing to do, only on his days off.

But his personality isn't all that's changed. He is larger, stronger, more like a dragon in appearance. His scales have darkened and his spines are crimson. His first, and for some time, only, friend is scared. Twilight wants to help, to figure out exactly what caused this shift and reverse it to have her little brother back, but when she delves into the only imaginable cure, the fabled "Harmony Magic," things only get worse.

With his innocence lost, and his best friend in the world being slowly "Harmonized," what in the world can Spike the glorified butler Dragon do?

Mystery tag may or may not apply, same with Thriller, not exactly sure what constitutes either.
Sex tag won't come into play until the "Harmonizing," and is until then, and even possibly after, SFW.
If anyone would like to help me by making cover art, I'd appreciate it, but until then, I'll work on my own.