Artemis: Eye of Gaea - The Cedric Series, #4

The quest to return the eye is still unfolding. Cedric, Angeline, Romasanta, and Nyctimus have crossed over into the Otherworld where spirits, faeries, and other strange creature live under the rule of the Halls of Gaea and many other forgotten titans. Again, Cedric finds himself separated from Angeline, but the words from a familiar face make him realize it may be for the best. Here in the Otherworld, you become your inner self.
True to this concept, Romasanta and Nyctimus are nothing more than men while Cedric has taken on a demonic form massive and wild. They now must travel through the levels of the Otherworld in order to reach the Hall of Freya and Gaea's domain. Can they find a way back to the Mortal Realm and when they get there, what has changed?