The Grimoire

A book of spells Joshuwa found (Luci needs to give details here I cannot find them in chat). It was originally possessed by The Guardian, a human magician who was part of The Coven that tried to uncover the mysteries of Thistlewood and harness them for magical power.

The most legible parts of the grimoire are the Guardian's personal diary, with notes on The Coven and his opinions on magic, updates on his activities and so on. This contains several crucial clues to uncovering the secrets of the town.

The grimoire does bestow magical power and Joshuwa can use it to perform a number of magical feats.

History
In episode 9 the Interns showed the grimoire to Jermaine Foster. He initially suggested that they burn it and seemed uncomfortable in the book's presence. He said no good would come of it. Fliss and Joshuwa struggled over the book as Fliss wanted to show Jermaine references to the coven member J to see if it could be him, and the book dropped open. When Jermaine touched it, the pages started burning and he couldn't let go, as Joshuwa took it back he tore skin off Jermaine's hand.