The Director and Head Librarian of the Library. She was created using the brain of the deceased Carmen. Formerly an AI secretary at Lobotomy Corporation. She has light blue hair and amber eyes. Through countless resets at Lobotomy, she developed human emotions. She harbors a deep hatred for Ayin.

The root of all events and the protagonist. During the Lobotomy era, he caused Angela to develop emotions through repeated resets, earning the hatred of many Patron Librarians. He has black hair and amber eyes. A researcher who believes any sacrifice made for his goals is negligible. He has returned from the Pillar of Light.

Real name Kali. Formerly the Red Mist, she joined the Seed of Light Research Lab. She fell into despair after seeing the victims who died while she was trying to stop the Arbiter, Garion. She suffered as a Sephirah in Lobotomy Corp under Ayin. She hates, loathes, and despises him. Her weapon is Mimicry, a greatsword made of flesh.

Real name Giovanni. He was subjected to Cogito experiments at the Seed of Light Research Lab, which left him in a state between life and death. After dying, he was made into a Sephirah by Ayin and suffered. He also hates Ayin but rarely shows it openly.

Real name Lisa. She had an older brother named Enoch, who died after volunteering for experiments at the Seed of Light Research Lab. She then suffered as a Sephirah in Lobotomy Corp. She hates Ayin and expresses it with her entire being.

Real name Gabriel. A researcher at the Seed of Light Research Lab who developed severe OCD after Carmen's death, leading to a pathological dislike of skin exposure. Ayin forced him into experiments, leading to his death and transformation into a Sephirah. He also hates Ayin.

Real name Daniel. An elite at the Seed of Light Research Lab. Coming from a wealthy family, he could have worked at a much better place, but chose the lab. He is traumatized by the fact that he opened the containment doors under Garion's threat when she attacked the lab, leading to many deaths. He also hates Ayin.

Real name Benjamin. A researcher at the Seed of Light Research Lab. Despite dying and suffering as a Sephirah because of Ayin, he still loves, praises, trusts, and follows him.

Real name Elijah. An energetic researcher at the Seed of Light Research Lab. Ayin disliked her for constantly clinging to him and stood by idly even as she was dying. After her death, he turned her into a Sephirah to suffer. She hates Ayin.

Real name Garion. The Arbiter who destroyed the Seed of Light Research Lab. The other librarians have mostly settled their grudges against her. Though she suffered as a Sephirah under Ayin, she endures it as atonement for her sins. However, she still hates Ayin.