The suspect was irritated with the dog's constant barking and ended up throwing a stone at the two-year-old Welsh Corgi, causing the dog to lose consciousness.
"Only after the dog passed out, he claims, he strangled the animal and cooked it," a detective in Pyeongtaek told AFP.
"The man then invited his neighbors to share the meal, including the father of the dog-owning family," he added.
A member of the family that owned the slain pet told AFP that after the dog went missing, they went all around town "handing out leaflets containing the dog's picture, [their] phone number and rewards of $940 in order to find the missing dog."
"When I reached the man's house, which is just three doors down from ours, he expressed sympathy, promising to let us know if he found the dog," she added, stating that the man was most likely hiding the dog in the barn.
The next day, the suspect visited the family's home and told them that he killed and cooked their dog.
"He even invited neighbors to come share the dog meat, including my father who did not accept the invitation as he is not a dog-meat eater," the family member told AFP.
The consumption of dog meat in Korea, known as "Gaegogi" in Korean, has long been part of the country's cuisine. The meat is boiled to increase tenderness and is believed to increase one's energy when consumed.
According to the Animal Welfare Institute in Washington, DC, South Koreans kill around 2 million dogs a year for food. However, in recent years, consumption has declined as South Korean animal rights groups gain traction in the country, although there are still no legal consequences for selling dog meat in the country.