The dog is one of the common animals around us and is known to have developed the closest relationship with us. Naturally gentle and intelligent, dogs love the company of humans who find their advanced olfactory and auditory senses very useful. Loyal and brave within their territory, dogs are on the alert for danger, showing great bravery. They become fiercely protective of their owner by showing hostility to strangers. As one of the oldest companions in human civilizations, the East or the West, the dog has long been the symbol of loyalty to man. Especially, the dog appearing in folktales or legends is remarkably loyal and righteous, proving its great loyalty by sacrificing its own life. Many tales, statues, and tombs commemorating a loyal dog can be found all over Korea. On the other hand, expressions of the dog have been frequently used to express lowliness or vulgarity in everyday life. "Seodanggae (compared to a lazy, unintelligent person)," "Maenggyeon (savage)," "Motdoen-gae (ill-tempered person)," "Miun-gae (hated person)," "Jeojil-gae (lowly person)," "Ttonggae (mongrel)," "Cheondeok-kkureogi-gae (despised person)" and the like are all derogatory terms. There are no other animals mentioned so frequently in Korean sayings. Anything bad or low in quality is prefixed with "gae," meaning "dog" in Korean. Cheaper or wild apricot is called "gae-salgu." A type of cockscomb is called "gae-maendeurami." In shamanistic myths, it is the white dog that guides the resurrected dead back to this life. Likewise, the Dog was understood as a medium connecting the otherworld and this life. Classical painters must have had dogs as their favorite subject matter. One of the expression techniques often involved transforming a picture image into a character. For example, the paintings "Hwajogujado (花鳥狗子圖, Painting of Flowers, Birds, and Puppies)" and "Mogyeondo (母犬圖, Painting of a Mother Dog) by Yi Am (李巖, 1499∼？) and "Heukgudo (黑狗圖, Painting of a Dog Scratching) by Kim Du-ryang (金斗樑, 1696~1763) feature dogs as the main subject under a tree. A dog under the tree, represented by the Chinese character "樹," symbolizes the dog's vigilance to protect a home. The dog is represented by the character "戌" and the tree "樹."

Traditionally in Korea, dogs played various roles -- keeping the house, hunting, guiding the blind and more; at the same time, however, they were believed to guard not only the physical but also spiritual entities, for the image was used as a guardian god and an evil deflector to bring fortune and happiness in the home. The Dog was believed to be able not only to dispel plagues, goblins, and ghosts but also protect people against them. "Samgukyusa (三國遺事, the Memorabilia of the Three Kingdoms)" records that, preceding the fall of the Baekje dynasty, dogs in Sabiseong wept despairingly. Therefore, if the house dog cried sadly, it was viewed as a bad omen, and the dog was immediately sold. In addition, if the house dog dug the ground for no apparent reason, it was thought to be digging its own grave, so the dog was removed from the house, after which a ceremonial rite to the gods was performed to pray for the safety of the family.

The Chinese character representing the Dog (戌) was believed to be similar to the character meaning "guard (守)," which reads as "su" in Korean. This is phonetically the same as the character meaning "tree (樹)," so they are often deemed to mean the same thing. Therefore, "Sul-su-su-su (戌戍樹守, a dog under the tree)" means "vigilance against thief." This kind of painting was believed to have the power to prevent theft. Such superstitious folk belief dates back to ancient dynasties. The image of the Dog, with a purpose of protecting the tomb, was painted on the left wall of the Front and Main Chambers of Gakjeochong ("Tombs of the Wrestlers") Tomb of the Goguryeo dynasty. Koreans in general have always loved and enjoyed the company of dogs; note, however, that the Korean word "gae" is used to compare or describe something or someone with low, vulgar traits. As another aspect of dogs in Korea, no matter how smart and lovable a dog may be, it was often mistreated; the animal, regarded as lowly and dirty, was left outside and fed leftover food only. The dog as a bright being, loyal and righteous, must be commemorated, versus the dog as a dark being, vulgar, abominable, and worthless. In Korea, such contrasting status of dogs, the symbol of loyalty or lowliness, was formed through folktales and customs.