Twilight Sparkle and her fellow Elements of Harmony have faced down supernatural foes of the highest order, but sometimes the deadliest danger can come from places one would least expect. As Twilight is forced to bear a devastating secret, her efforts to keep the Elements together may well tear them all apart.
The plotline of the thrilling Pony Psychology Series continues with an exploration of deception, despair and Discord.
This series takes place between Season Two and Season Three.
Secrets and Lies shares the Pony Psychology Series TVTropes page.

parasite [ˈpærəˌsaɪt]
noun
An animal or plant that lives in or on another (the host) from which it obtains nourishment. The host does not benefit from the association and is often harmed by it. In the case of some parasites they can take over the host body, controlling or morphing it to suite their inherent needs. Parasites are transmitted through many means: contact with an infected host, the sharing of liquids, and, in some cases, parasites may even hunt their intended prey.

Edited by:
Burraku_Pansa
and Millennial Dan

Cover art by:
finaglerific

As Featured on Equestria Daily:
http://www.equestriadaily.com/2012/05/story-of-parasites.html

The Ponyville Six visit Canterlot to watch Rainbow Dash participate in a long-distance race. However, a visit to Twilight's favourite donut shop results in the bookish Unicorn finding herself in a pitched donut-eating battle with a certain pink Party Pony, with disastrous results.

This short story was created as part of a writing audition for the Equestria Online MMO.
I hope you enjoy it as much as the game's staff apparently did! :D