a.k.a. Reynard (by Dora, during her madness)
A creature discovered with an insane human man at the edge of the pit into the crypts of Briarstone Asylum. He initially presented as a scared, filthy, and malnourished arctic fox.
After looking into the pit and seeing the thing below the earth, Dora immediately began caring for him like a child and gave it the name “Reynard.”
When Dora cast detect thoughts in Chapter 18, she learned that Reynard had an above average intelligence, a level almost entirely unknown for typical animals.
In Chapter 31, Reynard expressed great discomfort with the champagne fox that Ray decided to let follow the party.
In Chapter 34, it was revealed that the fox was actually a middle-aged Kitsune man with black and white striped hair. He was also suffering from mental trauma, but remembered a school, and a person—a spouse or lover—and a book, and then… worms. He came out of his transformed state on 3 Neth and met the party and other chapel survivors at Briarstone, where he had been a patient. Naysa recalled stories of him singing to the other patients.
In Chapter 43, it was observed that Barnabus had begun to lose his cheeriness, spending most of the day writing. There was a sense of dread about him, and he adopted his anthropomorphic form. He wept and wrote and hummed and slept—withdrawn and disturbed. But every time he saw Dora, he reverted to his human form to accommodate her.
During the solstice ceremonies in Chapter 49, he shared that his parents, Bassanio and Persephone, were crusaders in Kenabres, battling the cults of Baphomet. When he was twelve he was allowed to accompany the mercenary band, but they were betrayed by a man named Cororin. That was the first time he turned into a fox.
During the Skum attack on the Sellen Starling in Chapter 50 (Part 2), Barnabus was revealed to be a Skald, a melding of Barbarian and Bard with a song that can inspire combat rage in his companions.
In Chapter 51, it was revealed that Barnabus already knew the name of Carcosa, even before he saw the city with everyone else on the Sellen Starling during the botched “Great Harvest” ritual.
First Reference: Chapter 17
Other Notable References: Chapter 18, Chapter 22, Chapter 23, Chapter 27, Chapter 31, Chapter 34, Chapter 43, Chapter 49, Chapter 50 (Part 2), Chapter 51