Inflict not on an enemy every injury in your power, for he may afterwards become your friend.
Hah. So you got off on playing the hero, huh? The wolf who wanted to become the shepherd. How sickeningly noble.
"I'm going to join the Avatar, and I'm going to help him defeat you."
And what happened then?
Well, in Whoville, they say,
The Grinch's small heart
Grew three sizes that day.
"What is better - to be born good, or to overcome your evil nature through great effort?"
— Paarthurnax, The Elder Scrolls V: Skyrim
You think I'll betray you. And on any other day, you'd be right. The scientists were always hanging cores on me to regulate my behavior. I've heard voices all my life. But now I hear the voice of a conscience, and it's terrifying, because for the first time it's my voice. I'm being serious, I think there's something really wrong with me.
"Oh, hey, Grandpa, it's that guy who kidnapped your soul and then tried to kill me! But now he's our friend!"
—Yugi talking about Pegasus; Yu-Gi-Oh: Bonds Beyond Time The Abridged Movie
"I now know the true meaning of oppression, and have thus lost my taste for inflicting it."
"Barely even friends, then somebody bends, unexpectedly."
—Tale as old as time, Beauty and the Beast