Aqua is the most self-willed of the trio of protagonists in Birth by Sleep. She displays true elegance while fighting, and will do anything to protect her friends. When relaxed she can be very gregarious and comedic, but when angered, she can become bellicose. Aqua is remarkably even-tempered and dead-set on her goals, and only threats on her loved ones seem to make her lose her composure. Aqua is comedically insecure in a romantic sense.