A Houthi follower with fake blood on his clothes lies on the ground to represent a victim as others perform a war dance during a ceremony marking the first anniversary of the Houthi movement's takeover of Yemen's capital Sanaa September 21, 2015. (Photo by Khaled Abdullah/Reuters)

A participant smiles at the annual Christopher Street Day parade on Kurfuerstendamm in Berlin, Germany, June 27, 2015. (Photo by Fabrizio Bensch/Reuters)

A devotee smiles as she offers prayers during the Swasthani Brata Katha festival in Kathmandu, Nepal January 12, 2017. (Photo by Navesh Chitrakar/Reuters)

A girl smiles during the celebration of Holi at the Art Department of the University of Dhaka in Dhaka, Bangladesh on March 8, 2023. (Photo by Mohammad Ponir Hossain/Reuters)

This bat gives a cheeky smile as he gobbles down his food at Singapore Zoo, on September 10, 2013. (Photo by Benny Iskander/HotSpot Media)

Animal rights activists covered with fake blood sit on the floor during a protest against the use of animals in research to mark World Day for Animals in Laboratories in central Madrid April 24, 2014. The sign reads, “How many rabbits do your shampoo kill?”. (Photo by Andrea Comas/Reuters)

The Belgian photographer Anton Kusters spent two years photographing the Yakuza, Japan’s most notorious gang. He returned with some amazing images that he made into a book called “Odo Yakuza Tokyo”. (Odo means “the way of the cherry blossom” and is the credo of the Yakuza family he followed. Photo: An erotic danser picks up fake 2-dollar bills during a private dance with a Yakuza customer in a strip tease bar in Kabukicho, a bar which is controlled by the ODO family – 2010. (Photo and caption by Anton Kusters)

To mark Halloween, 150 teens descended upon a swimming pool in Essex to help mobile network giffgaff recreate the famous Tomatina tomato fight... only this time, with blood and guts. Different takes #giffgaffguts. On October 18, 2013 in Dagenham, England. (Photo by Dave J. Hogan/Stringer for giffgaff)