The Antagonist Boy X Boy

I am the antagonist.
My job is to make you suffer, to make you give up.
So then why does it pain me to harm you?

What if characters of a book lived in their own reality? The protagonist, antagonist, heroine, love interest, secondary characters, all aware of themselves in the novel, but forced to play their roles. What if for some reason one of them decided to change? What if the villain decided to choose love over pain and break all the rules?