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Historically, Komainu are a pair of stone lion statues placed outside shrines to guard against evil spirits. One of the pair always has an open mouth and the other a closed one (as if saying 'a' and 'um', the beginning and end of the Sanskrit alphabet). Together they form the sound of 'aum', a sacred sound used in Buddhism and Hinduism, symbolising the beginning and end of all things. Their origins are from India initially, but then spread to China, Korea and Japan.