Bertrand Demay, who calls himself Beb-Deum, studied applied arts in Paris. In 1982, he debuted in Métal Hurlant magazine with his first short stories. Some of these comics were collected in the album 'L'Album', that was published by Les Humanoïdes Associés in 1987. In 1987 he created 'Bürocratika', a futuristic story inspired by Terry Gilliam's movie Brazil. With scenarist Jean-Pierre Dionnet he produced 'Région Étrangère' in 1989 and 'Ma Vie est un Bouquet de Violettes', which was prepublished in L'Écho des Savanes. Together with Marie-Ange Guillaume, Beb-Deum created 'Surgir de l'Onde'.
He worked also for the Japanese publisher Kodansha and the magazine Morning, in which he published 'La Théorie des Dominos'. At P.M.J. Éditions, he produced 'Éloge de la Moue' in 1999 and 'E-Dad' in 2000. He was also present on the juvenile market, with 'Un Pingouin sous les Étoiles' (text by Jackie Landreaux-Valabrèque') and 'On ne Joue Plus Roméo' (text by Anne-Marie Pol), both published by Hachette Presse, and 'PK - Douze voyages en Centrafrique' at Édition du Rouergue.