Of this list of questions: http://writerswrite.co.za/15-questions-authors-should-ask-characters
I’ve always been a fan of doing character interviews. I do them of my major characters in each book. Along with questions like, “What would cause you to abandon your plan?” for the antagonist (as in, “Does he do it because he wants to make the world better, as he sees it–and thus is a well-meaning extremist. Or is he just in it for Global Domination and the EVULZ). Even minor characters get a good helping of these questions. You never know when one might ‘step up’ on you.
For Yalissa, in my Hellenistic Fantasy, for instance. What would mentally destroy her has changed from Book 1 to now. In the 1st, the Destruction of her Temple and Faith would have undone her. She would have sacrificed everything for her fellow Chosen. However, the events of the second book tear away all of that from her. Now, her relationship to Sharit is more open to questioning. And what she truly cares for is the people she has freed from captivity.
How did she get from point A to Point C? Ahh. Not telling. lol. One day you’ll learn. I hope. 😉