Arona is child-like and quite gullible, often falling for Sensei's jokes. Arona thoroughly enjoys sweets, quick to abandon a diet for the sake of sweets—or even breaking into tears from being denied them.

Plana generally spoke with simple commands, such as "understood." However, after parting with Phrenapates, she begins speaking more normally, though she often still speaks like a stereotypical computer AI by using simple formal response phrases. Plana is glum and formal, reserved, melancholic.