The First of the Fallen is a character from the Hellblazer mythos. Also known as Satan, he is the nigh-omnipotent ruler of Hell and the embodiment of sin and evil. He is also one of John Constantine's most enduring archenemies.
A Blue's musician, by the name of Willie Cole, sold his soul to The First for an unknown reason. After a period of time, The First came to claim Willie's soul, while the latter was recording in a studio. The First's voice ended up being recorded on an acetate.