Gilles de Rais (Into the Crypts of Rays)

Gilles de Rais is was an infamous serial killer real and aristocrat that served the Hundred Years Wars.

History
After the war, he left militarism and began to take an interest in black magic and mythicism. How Gilles began kidnapping countless children and killing all children and sacrificing them to demons. And eventually he was responsible for the deaths of over 140 children that he killed by sacrificing them for the demon, he was later eventually arrested and sentenced to death for sexual abuse and the deaths of 140 children.