Ernest Crosby is a tall man with long reddish brown hair that is pulled back. He also has brown eyes with glasses. While he worked at William's school, he wore a white robe with gold lining around the collar.
At first Ernest comes across as a calm, kind man who cares deeply about his students. However, after Stiri is revealed to be a demon to him, he reveals a new side of himself. This side is cruel and heartless, willing to destroy even his own students if they get in his way. His hatred towards demons is unknown, though it may have something to do in his past, as he was and still is suspicious of everyone around him.
- Ernest very different from many of the other antagonists in this series, as he aims to destroy William rather than change him to support heaven.
- However, Uriel also does not aim to convert William. Rather, Uriel wants to protect William.
- This would make Ernest the only antagonist who wants to destroy William.
Amon and Mamon • Baphomet • Eligos • Gilles de Rais • Gilgamesh • John Dee • Lamia • Leonard
Belphegor • Empusa • Lamashtu • Leviathan • Lucifel Rofocale • Pluto • Astaroth the Second • Behemoth
Adrian Swallow • Barton Twining • Bianca Clifford • Elliot Eden • Mary • William Wynn Westcott
Arthur Christian • Cassandra • Ernest Crosby • Tamar • Elizabeth Dale