John Fontaine is a tall dark-skinned man of above-average height, thin with no hair on his head. When on missions for Alchem, he is often seen wearing a canvas trench coat, with a full face mask that reveals only one eye covered by a red lens.
Loyal to his work, Fontaine is a quiet, often overlooked individual. He speaks bluntly and to-the-point, holding distaste for those who use honeyed words and charisma to get their way. Fontaine is rather intelligent as well, though he's only ever needed to put it to use for militaristic purposes. A calm individual, he is only ever brought to real anger in the event of a life-or-death situation.
John Fontaine and his twin brother Aaron were born in Silivia to an unmarried couple. Their father was an experienced Alchemilia soldier. Once they were of age, the twins would also find employment at Alchemilia.
Due to a hard-working mindset and a willingness to complete any task assigned to him, Fontaine quickly rose through the ranks. By 319, he could enter Gimel-tier restricted areas and regularly met with Gabriel Alchemilia.
- The Dream Eater Xanvi impersonated Fontaine after his death in the episodes spanning from "Carpe Diem" to "Don't Fear the Reaper."