Death by Ecstasy

Death by Ecstasy is a novella in the Known Space universe by Larry Niven. It is the first of five Gil Hamilton detective stories, and provides most of the backstory for the character.

A belter, Owen Jennison, is found dead on Earth in a locked Los Angeles apartment. His death is an apparent suicide. Hamilton, a friend and former crewmate of Jennison, is called to the scene to investigate. He finds Owen with a droud (a wirehead's transformer) plugged into the back of his head. The latter apparently starved himself to death while continuously stimulating the pleasure center of his own brain.

Hamilton, refusing to believe that his friend would commit suicide or turn wirehead, suspects foul play.