What is a pachinko machine?
Pachinko
Pachinko(パチンコ) is a type of mechanical game originating in Japan and is used as both a form of recreational arcade game and much more frequently as a gambling device, filling a Japanese gambling niche comparable to that of the slot machine in Western gaming.
Advantage gambling
In the Japanese game of pachinko, there are numerous purported strategies for winning, the most reliable of which is to use inside information to learn which machines have the highest payout settings. Because of the "Stock", "Renchan", and "tenjō" systems, it is possible to make money by simply playing machines on which someone has just lost a huge amount of money. This is called being a "hyena". They are easy to recognize, roaming the aisles for a "Kamo" ("sucker" in English) to leave their machine in a favorable mode.