Passengers travel on the London train and underground system during the Christmas party season, December 18, 2015. (Photo by Paul Hackett/Reuters)

Passengers pose for a selfie as they wait for the Night Tube train service at Oxford Circus on the London underground system in London, Britain August 20, 2016. The London Underground is starting its first-ever overnight service, a move city leaders hope will make the British capital a truly 24-hour city and bolster the local economy. (Photo by Paul Hackett/Reuters)

A visitor relaxes in a sleeping module at Tokyo's tube Hotel “Capsule Inn Akihabara” on February 6, 2007 in Tokyo, Japan. The two-square-meter sleep modules are equipped with a TV, Radio and Wireless LAN and are priced at 3500 yen per night. Uptil recently it has mainly been the office workers who stay at such tube hotels when they cannot go home, but recently they are attracting many foreign travellers due to their Japanese style. (Photo by Koichi Kamoshida/Getty Images)

«Underwater». Laurie Simmons discovered this silicone sеx doll in a shop while on holiday in Japan and was immediately interested in the type of generic beauty their looks could add to her work. She went on to create the Love Doll series, in which she places silicone sеx dolls in positions that explore a woman’s interior life. (Photo by Laurie Simmons/Salon 94/The Guardian)

Actresses Vonnie Lui (R) and Yukiku Suou (L) attend the “3D s*x And Zen: Extreme Ecstacy” photocall at the Majestic Beach Pier during the 64th Cannes Film Festival on May 14, 2011 in Cannes, France. (Photo by Michael Buckner/Getty Images)

Li Tingting, second from right, laughs as she is lifted off the ground by her wife Teresa Xu, right, outside of a beauty salon where the two were preparing for their wedding as clerks from an adjacent shop look on in Beijing, Thursday, July 2, 2015. Li, a 25-year-old prominent women's rights activist who was released from detention in April, held the wedding ceremony with her partner Teresa on Thursday and announced their marriage in an effort to push for LGBT (lesbian, gay, bisexual, and transgender) rights in China. (Photo by Mark Schiefelbein/AP Photo)

An exotic model poses for photographs at a news conference to promote the “Expo Sеx and Eroticism” adult exhibition in Mexico City, Mexico March 1, 2017. (Photo by Carlos Jasso/Reuters)

These are some of the Real Doll bodies made by Abyss Creations being assembled in the factory on Tuesday, September 12, 2017 in San Marcos, California. Customers can dictate their partner’s character by choosing between 18 personality traits including shy, sensual, jealous, moody or talkative. (Photo by Eduardo Contreras/San Diego Union-Tribune via ZUMA/Rex Features/Shutterstock)