Soldiers from Japan's Ground Self Defense Force come ashore in amphibious assault vehicle as they train alongside U.S. Marines during the bilateral annual Iron Fist military training exercise in Camp Pendleton, California February 26, 2016. (Photo by Mike Blake/Reuters)

Mature woman lying on bed, rear view. (Photo by Andersen Ross/Getty Images)

Germany, Business couple making love under desk. (Photo by Roman Maerzinger/Getty Images)

Women in lingerie touching each other. (Photo by BDLM/Getty Images)

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

Portrait beautiful woman on the beach, Landing aircraft above the beach at Phuket Airport. Mai Khao beach, one of the most popular beaches among tourists in Phuket. (Photo by Southtownboy/Getty Images/iStockphoto)

A Polish Army tank takes part in the NATO Noble Jump exercise on a training range near Swietoszow Zagan, Poland, Thursday, June 18, 2015. (AP Photo/Alik Keplicz)

Police take part in a role play exercise as they clear a protest on top of a train during training on March 6, 2012 in Oxenhope, England. A new team of specialist officers set up to deal with searches and policing at a height, such as on top of a train, undergo training exercise in Oxenhope, West Yorkshire. (Photo by Bethany Clarke/Getty Images)