As the First Secretary of Mayor Henry MacDowell, Ernest Reis was a tutor to the mayor's granddaughter, Elie MacDowell. Ever since she started to study abroad, they have grown estranged to each other. Ernest tried to pursue Elie to follow a political career, but her mind was set on that of the police force. Ernest said he would still look over her.
Ernest originally aimed to follow in Mayor MacDowell's footsteps by maintaining a neutral political position. Due to the difficulties that came with the position, however, he misappropriated the office's funds for years to strengthen his ties with the pro-Imperialist faction within the government.
The Gnosis provided by Joachim Guenter manipulated Ernest into an assassination attempt on his boss, Mayor Henry MacDowell. The attempt failed, however, thanks to the intervention of the Special Support Section.
The Gnosis that were prescribed to Ernest allowed him to Demonise and easily break out of prison. He became an underling of Joachim, wielding a ghastly devil sword in one hand. As a side effect of the Gnosis, his eyes had turned crimson red. He transformed into another kind of demon, but was once again defeated by the SSS.
Zero and Ao no Kiseki