Léon Signoret is an art student from Chevigny-Saint-Sauveur, the son of a small-time French mustard manufacturer. Creative and a bit chaotic, he is full of energy, though lacking in the violent and criminal tendencies of his employer, Sir Di Grimani. He speaks with a heavy French accent and has luscious long hair, which is very attractive to some of the visiting ladies.

To support his studies, he is occasionally hired as a preparateur, or art handler in The Night's Watch Gallery. He installs exhibitions, handles artworks, and packs and unpacks artworks. All of this requires highly specialised practical skill set, to ensure that works are displayed in optimal conditions.

As a privilege of his part time job, he has been given a part of the Di Grimani's art studio to work in during the daytime