Mud-covered tourists pretend to be trapped inside a mud prison at the Daecheon Beach Mud Plaza in the city of Boryeong on South Korea's west coast, July 17, as they take part in the Boryeong Mud Festival, which opened that day and runs through July 26. Boryeong mud is rich in natural mineral component and is considered to prevent skin aging. (Photo by EPA/Yonhap)

A Zombie Santa is pictured Death Yard Haunted Attraction in Hendersonville, Tennessee December 10, 2014. The Nashville-area haunted house is getting into the Christmas spirit this weekend, with Zombie Santa, his undead elves and a demonic reindeer going on the attack for fun and charity. (Photo by Harrison McClary/Reuters)

Woman and man playing domination games in bed. (Photo by NDAB Creativity/Rex Features/Shutterstock)

Goyo, an eight-month-old mini pig, plays with a dog in Mexico City, December 21, 2015. Mini pigs can grow to about 30 kg (66.1 lbs) in weight and about 35 cm (1.1 ft) in height, according to the company Mini Pigs Mexico. The company says that the mini pigs' popularity as pets is growing and around 300 are sold every year in Mexico, with prices ranging from $350 to $1,600. (Photo by Edgard Garrido/Reuters)

A picture made available on 08 February 2017 shows staff playing with cats inside the Super Very Very Important Cat (VVIC) room at the CATZONIA cat hotel in Damansara, outside Kuala Lumpur, Malaysia, 07 February 2017. (Photo by Fazry Ismail/EPA)

In this Sunday, March 12, 2017, picture a Don Sphinx cat reaches for a judge while being evaluated, in Bucharest, Romania. More than 1,500 dogs and 150 cats from twelve countries were evaluated during a three day pet show and competition in the Romanian capital. (Photo by Vadim Ghirda/AP Photo)

In a photo taken on August 30, 2014 a man brushes his dog as he waits to take part in a competition at a dog show in Seoul. Some 2000 dogs took part in the three-day show organised by the Korea Kennel Federation which was celebrating its 58th anniversary. Dog ownership in South Korea is a growing industry widely reported to have passed 10 million in 2013, with private expenditure on pet supplies increasing some 14 percent per year since 2000, according to a report by the Nonghyup Economic Research Institute. (Photo by Ed Jones/AFP Photo)