Stray dogs stand on tombs in Diamond Hill cemetery in Hong Kong, China, 04 April 2017. According to the lunar calendar, the Qingming Festival is observed on 04 April . The Qingming Festival, also known as Tomb-Sweeping Day, is marked by Chinese people by going to the cemetery to cleaning up tombs, bring flowers, and making offerings to their ancestors. (Photo by Jerome Favre/EPA)

A combination photograph shows revelers dressed in "Dia de Muertos" or "Day of the Dead" themes as they pose for photos while taking part in the Greenwich Village Halloween Parade in the Manhattan borough of New York October 31, 2015. (Photo by Carlo Allegri/Reuters)

A musician plays his violin next to a depiction of La Santa Muerte (Saint Death) at a shrine during Day of the Dead celebrations in Ciudad Juarez, Mexico, November 2, 2015. (Photo by Jose Luis Gonzalez/Reuters)

Cat-Friend vs Dog-Friend, Two Humans Acting Like House Pets

Wladimir Klitschko (L) and David Haye attend a press conference on June 27, 2011 in Hamburg, Germany to preview the heavy weight title fight between them which will be held on the 2nd July 2011 at the Imtech Arena. (Photo by Scott Heavey/Getty Images)

“Ben Heine (born 12 June 1983 Abidjan, Ivory coast) is a Belgian multidisciplinary artist. Starting as a painter and political cartoonist, he became more widely known in 2011 for his “Pencil vs Camera” and “Digital Circlism” projects”. – Wikipedia (Photo by Ben Heine; Source: Flickr)

Pope Benedict XVI arrives at the Santa Sabina Basilica for the Ash Wednesday service on March 9, 2011 in Rome, Italy. Ash Wednesday opens the liturgical 40-day period of Lent, a period of prayer, fasting, penitence and alms giving leading up to Easter.

Revellers celebrate "Ash Monday" by participating in a colourful "flour war", a traditional festivity marking the end of the carnival season and the start of the 40-day Lent period until the Orthodox Easter,in the port town of Galaxidi, some 215 km (134 miles) north west of Athens, March 18, 2013. The revellers "fight" by throwing coloured flour, charcoal dust and powder painting until they essentially run out of supplies. (Photo by Yannis Behrakis/Reuters)