Astil Manuscript

The Astil Manuscript or Sora is a legendary grimoire said to contain information about another world. Originally belonging to Hijiri, Sora has since contracted with Arata, supporting and protecting him after becoming a magus.

Personality
Sora goes along with Arata's personality and actions with enthusiasm if nothing else, cheerfully noting she doesn't dislike having a master like him, despite his perversion and carelessness. If anything, she actually enjoys having him as a master, since it seems that his behavior entertains her. She's also not unwilling to go along with this behavior herself, much like Levi and Liese.

She seems to have been quite loyal to Hijiri as well, honoring her wish to take care of Arata even when she no longer can. Though, since she's likely known Arata for a very long time before he knew of her existence, it could be argued she wanted to protect him as much as her former master did.

She's roughly as hyperactive and rash as her current master, in that she always leaves herself open after using a powerful attack, and seems if anything too confident in her powers, not that her immense strength as a Grimoire doesn't give her the right to be.

Ironic for a being whose human form is likely nothing more than a composite, she can actually become embarrassed, as when Astral Trinity erased her magic, stripping her naked, she also expressed shock and disbelief that he'd actually attack his own grimoire.

Appearance
Sora's true form is as a small, ornate book, bound with chains. She can also assume human form. Sora's usual human form appears as a short and somewhat immature individual young woman, dressed in black, all in all, she has a loli appearance, as it would be described. She also has grey-white hair with a black ribbon therein.

Abilities
Being a powerful and ancient Grimoire, the Astil Manuscript, "Sora" is capable of unleashing immense magical power, destroying her surroundings and destroying large groups of spectres in one burst. She has repeatedly shown the ability, with Arata, to analyze and modify other people's magic for her current master's use, though it's implied the ability to do so is her masters, she is the one who most understands the process and how it's done. She was also able to reconstruct.

Sora is prone to always leaving an opening after using a strong magic attack.

Scarlet Geburah
Is the most powerful named attack Sora has used thus far, it creates a powerful wave of destructive magic, which stands on par with Arata's "Meteor Punisher" and Mira's "White Universe" respectively.