Etienne Simon, better known as Yuio, started out as the colorist of series like 'Célestin Spéculoos' and 'Pedro le Coati'. He drew several comics for the French agency Corporate Fiction and the Belgian collection Artis Historia, and illustrated educational material. In 2004, he teamed up with writer Dav and began the gag series 'Trikäär' in Spirou.