In February, the Japanese hold a rather unique, informal ceremony at their homes called Setsubun. This involves the members of the family getting together and scattering beans around the house to drive away demons and evil spirits. One or two of the members of the household - usually the unlucky dad, for example - is chosen to be the demon. He puts on an oni mask (explained below) and runs around the house, making sure to hit each room, while the rest of the family pelts him with handfuls of dry soybeans, chanting "Oni wa soto, fuku wa uchi," or "demons out, good luck in!"
After the pelting is done, each member of the family has to eat a number of soybeans equivalent to their age.