Three members of English pop group The Tremeloes; Chip Hawkes, Alan Blakley and Dave Munden, kissing their brides; Carol Dilworth, Lyn Stevens and Andree Wittenberg, in Trafalgar Square, London. (Photo by Wesley/Getty Images). 1967

Eurovision fans from Sweden kiss in front of the Globen Arena prior the first the Eurovision Song Contest final in Stockholm, Sweden, Saturday, May 14, 2016. (Photo by Martin Meissner/AP Photo)

A mural signed by “TV Boy” and depicting Pope Francis and U.S. President Donald Trump kissing, is seen on a wall in downtown Rome, Italy on May 11, 2017. (Photo by Tony Gentile/Reuters)

Two women kiss each other during a flashmob on the ocassion of the International Day Against Homophobia, Transphobia and Biphobia in Pamplona, Navarra, Spain, 17 May 2017. The International Day Against Homophobia, Transphobia and Biphobia is held every year on 17 May. (Photo by Villar Lopez/EPA/EFE)

Members of the LGBT community kiss during a Kissathon to celebrate International Day Against Homophobia, outside Bellas Artes museum in Mexico City, Mexico, May 17, 2016. (Photo by Edgard Garrido/Reuters)

In this Thursday, May 16, 2013 file photo, Finland's Krista Siegfrids, second right, kisses a dancer as she performs her song “Marry Me” during the second semifinal of the Eurovision Song Contest at the Malmo Arena in Malmo, Sweden. That was the first girl-on-girl kiss in the history of the annual competition. Previously, organizers had sought to prevent similar embraces citing the competition's status as a family event. (Photo by Alastair Grant/AP Photo)

Dominic Bergamin, left, a new Vatican Swiss Guard, is is kissed by his wife Joanne, prior to a swearing-in ceremony, at the Vatican, Wednesday, May 6, 2015. The ceremony is held each May 6 to commemorate the day in 1527 when 147 Swiss Guards died protecting Pope Clement VII during the Sack of Rome. (Photo by Ettore Ferrari/AP Photo/Pool Photo)