Morningstar

Personality: unyielding and naughty. Uses Kawachi accent for some reason.
Likes: chocolate parfait and Hoshikage (seems to be some kind of ninja anime). Dislikes: liars.

This is a kind of a multi-functional virtual pet called "Cyber ​​Angel" who lives in Sayone's PC.
Her father is the developer of this "program", and Sayone has to test it, so you get to choose either Skyeye or Morningstar to be your (Sayone's) virtual pet during the game.
You can also choose to name them how you want, they don't even have a gender, so you can choose any name at all.