The blood in the bathtub scene with Caroline Faivre is actually a mixture of syrup of blackcurrant and cheap red wine.
The images were entirely made digitally. At first, director Rock Brenner wanted to photo shoot the film with a Lomography camera, but the camera broke at the very first day of shooting. Brenner wanted a special grain for this film, so he randomly began to film his computer screen with his digital camera; he found the result pretty strange and convincing. "Lettres de suicide" is actually a screener of the director's own computer.