Twilight has always considered herself the purest of intellectuals.
She has never felt remorse for her studies, because she has never had anything to be remorseful on.
All dissections were performed upon organisms that had died of natural causes, and any experimentation on live animals has always been done with the help of Fluttershy, to assure the best possible conditions.
But now, she's found a strange something in her small town that she calls home. A something that may change her, and may change how she works, forever.

This is an idea I had out of the blue whilst watching Markiplier. (Yes, TwattyCake, I like Markiplier and I will mention him every chance I get. Deal with it.) It's essentially a reversal of Responsibilities, which is on my user page because it's by me. So I don't have to give credit for my own ideas. Suck it, copyrights!