Mr L Prosser was a council worker who tried to demolish, and eventually succeeded in levelling, Arthur Dent's house.
Mr. Prosser was "only human" and was a direct male-line descendant of Genghis Khan, although "the only vestiges left of his mighty ancestry were a pronounced stoutness about the tum and a predilection for little fur hats".
In the first novel, Mr. Prosser was described as "forty, fat, and shabby". He was a "nervous, worried man". One thing he was especially nervous about was the demolition of Arthur Dent's house. He wore a fur hat, which was somewhat reminiscent of Genghis Khan's own.
Mr. Prosser liked axes, unlike his rose-fancying wife. Mr Prosser's dream home was a home well away from all problems but right near a pub.
Behind the scenes
On radio, he was played by Bill Wallis, on television by Joe Melia, and he was played by Steve Pemberton in the movie version.
He appeared in Fit the Twenty-Sixth of the radio series, despite not appearing in the novel Mostly Harmless, voiced by Bruce Hyman; this Prosser exists on a parallel Earth where the cottage he wishes to demolish is the home of both Arthur Dent and Fenchurch.