The "Devil's Chair" is a legendary device, found in urban legends, but likely dating back to ancient folklore - often the "Devil's Chair" is a decorative statue in the form of a chair or bench situated in a graveyard (originally as a monument or a place for mourners to rest): over time local legends would arise surrounding these statues and many young people would devise fiendish tales about the "Devil's Chair". It even coined the term devil’s chair (or "Haunted Chair") in folklore.
Some famous "Devil's Chairs" have a duel purpose of either rewarding the brave for daring to sit on them (normally at night) or cursing them for daring to commit such an act: some stories state that the "Devil's Chair" will give whoever sits on it bad luck and another more extreme legend states that if one sits too long on a particularly notorious "Devil's Chair" hands will come out of the ground and drag the victim to the underworld.
A slightly less terrible fate can be expected from another "Devil's Chair", which - according to local belief - will allow anyone who sits on it long enough to be visited by The Devil himself (which seems to be another reference to older folklore and the idea of witchcraft and devil-worship).
Some carved chairs, because of that myth itself, were probably not intended for use as anything but monuments, while the "monubench" is still commercially available. Once the original purpose of these chairs fell out of fashion, superstitions developed in association with the act of sitting in them. In a typical example, local young people dare one another to visit the site, most often after dark, at midnight, or on some specified night such as Halloween or New Year’s Eve.
Variously, the stories suggest the person brave enough to sit in the chair at such a time may be punished for impudence or rewarded for courage.