Isanami's unusual childish behaviour makes more sense when you realize that making her sad or afraid could make her disintegrate everything around her. Raising her in an ivory tower might have been thought of as a good idea.
In the manga, Anastasia's strange temporary clumsiness while dealing with Ichimaru and Niko during her introduction makes more sense once it is revealed they were actually working for the same guy at the moment.
Anastasia betrayal makes more sense when the initial purpose of the Braves were revealed: They're destined to die. She doesn't want to.
