Although the lion is native to southern Asia, as well as the plains of Africa, its appearance in the art of Japan was originally limited to the temple guardians and fantastic leonine mounts of various Buddhist deities, particularly the bodhisattva Monju. As in many other cultures, lions symbolized kingly power, particularly the supreme power of the Buddha's wisdom. Indeed, they are said to guard Buddhism and defend its laws.

The Japanese portrayal of these beasts was based on Chinese depictions, hence the Japanese name karashishi or "Chinese lion," though for the Chinese this creature was equally mysterious. Their representation of lions was derived from Indian Buddhist examples which were already stylized. Still, Chinese interpretations took on attributes of native tigers and the Pekinese dog, which was the pride of the Chinese Imperial family. They are characterized by large, imposing eyes, curly mane and tail, spotted coat and their fierce yet playful demeanor.

Pairs of guardian lions are said to protect the Buddha's throne and statues representing then have traditionally stood guard outside sacred buildings and temple precincts. Indeed, the Japanese refer to these guardian figures as koma inu implying "lion-dog guardian figures." As their use became increasingly secularized, guardians were placed in front of palaces, mansions and tombs, as well.

Similar to the anthropomorphic guardian figures known as nyo4, each pair of koma inu is depicted one with mouth closed and the other with mouth open, suggestive of the inhalation and exhalation of the heavenly force and the inextricable balance of yin and yang.