Afasys

Afasys (アファシス), alternatively spelled as ArFA-Sys in Western localisations, is an original Sword Art Online game character and the Protagonist's personal companion in Sword Art Online: Fatal Bullet. Afasys is a rare type, modeled Type-X, of an Artificial Intelligence (AI) companion called the Artificial Financial Adviser System and her full ID is Afa System Type-X A290-00. Due to Afasys only allowing the Protagonist to use Afasys's official name, the companion was nicknamed as Rei (零) by Leafa in reference to the zeros appended to her Unit ID.

Gun Gale Online
Both female (canon) and male (alternative) versions of Afasys feature white and purple prominently as their canon looks. They both have purple eyes, white hair and a skin-tight, purple-on-white suit. While the female Afasys has short and straight hair, the male Afasys variant has short and messy hair.

Personality
As a Type-X Unit, Afasys features a distinct personality, unlike the other models. Afasys is a clumsy companion who tends to make simple mistakes while handling a task, and is very forgetful in terms of remembering key information. As an AI companion, their battle personality can be adjusted by the Protagonist to suit their needs based on various parameters. While Afasys' core personality traits are predetermined, how they express themselves can also be adjusted by the Protagonist to sound bright, stoic, cute, zealous, or serious.

With the addition of the first DLC, Champion of Gunfire, situational emotes have been added as adjustable parameters that allow Protagonist to decide how Afasys reacts to certain events, such as waving when the Protagonist meets a friend, or pumping their fist up in the air upon leveling up.