[Ama-no-jaku are one of the few creatures in Japanese folklore that are a “type” of oni–most oni are just oni. In Pathfinder RPG, each oni are associated with a different type of humanoid or giant. So making these stealthy, small oni associated with halflings seemed a logical step]
Oni, Ama-no-jaku
This grinning red-skinned fiend stands only half as high as a
human, but its sharp teeth and claws suggest it is not to be trifled
with.
Ama-no-jaku are among the least of the oni, but they are no less
perverse and sadistic for it. Ama-no-jaku are typically obsessed with
wealth, preferring to gain prestige through covetous actions rather than
assuming places of authority in human societies. They are typically
wanderers, moving into a community long enough to steal its greatest
treasures and leave strife and distrust in its wake.
Ama-no-jaku are the incarnate forms of small and petty spirits, and
their forms are similarly stunted compared to their mighty kin. They
have a special affinity for halflings, joining in their traveling
caravans and using words and magic to draw the little folk towards crime
and treachery. All ama-no-jaku can read thoughts, and typically use
this ability in order to determine the greatest desires of humanoid
victims. They then use their suggestion abilities to force their victims
to act on these desires, delighting in the conflicts that arise.
An ama-no-jaku stands only three feet tall, but is monstrously strong for its size.
Shores of Swords 