Origin
Warau Salesman
Fukuzou Moguro, a traveling salesman, and his current customer. Moguro deals in things that give his customers their heart's desire, and once his deals are made and their unhealthy desires are satisfied, Moguro's customers are often left with terrible repercussions, especially if they break the rules of his deals...
The Laughing Salesman
The Laughing Salesman is a horror manga created by Fujiko Fujio A. The manga began as a one-shot series serialized in Shogakukan's Big Comic magazine on 1968, later becoming a full-fledged series published by Jitsugyo no Nihon Sha's Manga Sunday magazine from 1969 to 1971. The manga tells the story of a salesman named Moguro Fukuzo, whose job is to help people fill gaps in their soul. However, in reality, he ruins people's lives if his clients backstab him or never ask him for help in the first place.
