Fire Emblem - Azura and Kamui

Xerneas, no! D:

What does this mean? Is it…

A: Kamui does not have full control of this form? Did Kamui enter a berserk state, or are they being brainwashed by someone or something.

B: Aqua is secretly an antagonist. Kamui discovered this and is trying to stop her?

C: This is their S-Support and Aqua is in to this kind of stuff?