Benoît Ers was born in Liège, Belgium. He spent part of his childhood in Ivory Coast because of his father's work, and eventually settled in Sussy-en-Brie, France. He enrolled at the School of Fine Arts in Epinal after winning a scholarship at the Angoulême Comics Festival. He dropped out of school after six months, however, and returned to Liège to become an independent artist. He became the assistant of Olivier Saive and was an illustrator for the magazine of the Belgian federation of underwater research and activity.
He eventually illustrated some editorial sections in Spirou magazine, where he first met his future accomplice Dugomier. After some short stories for Spirou, Ers and Dugomier created the series 'Muriel et Boulon' for Lombard from 1995 to 2001. They returned to the pages of Spirou with the semi-realistic and supernatural series 'Les Démons d'Alexia' from 2004 to 2011, and then went back to Lombard for the creation of 'Hell School' in 2013.
Ers additionally launched 'Beauté Fatale' with Jean-Louis Janssens, a humorous series set in a beauty parlor (Vents d'Ouest, 2009-2010). He draws the thriller series 'Tueurs de mamans' together with Ludo Borecki from scripts by Zidrou for Dupuis from 2013.