Le Baron Noir (the Black Baron) is a very suiting name for a Belgian man of nobility that funded, supported and fomented a fascist underground, which was involved in all kinds of suspicious and criminal activities during the Cold War. It is even more fitting for a Belgian man of nobility that has been directly accused of the abuse and in one case of murder of children by no less than five victim-witnesses. That man is Benoit de Bonvoisin.
X1 apparently witnessed Carine "Clo" Dellaert's murder, at which she saw similar people involved in murders of other girls. The life of Carine is briefly examined and X1's testimony is determined to have been credible.
"I met Nihoul in a restaurant in Brussels. 'I am the Monster of Belgium,' he roared at me by way of greeting. He is confident he will never come to trial and that the evidence against him will never be heard by any jury. During the course of our meal he, apparently playfully, grabbed me, tickling, and finally pulled me over on to him in the restaurant booth until I had to appeal to my colleagues for rescue." (May 5, 2002, Olenka Frenkiel for The Guardian, 'Belgium's silent heart of darkness')
All roads in the Dutroux affair, lead to Jean-Michel Nihoul.