This was the first kiss ever filmed: Eadweard Muybridge used film to study the ways that humans and other animals move. The humans in his photographs were naked so that viewers could see how the body moved as his models walked, played sports, and kissed. American social conventions of the time prevented Muybridge from filming naked men in the same frames with naked women, and so when he photographed pairs of people, they were same-sex pairs so when he filmed a kiss, it was between 2 women.
Pinturicchio. Madonna and Child. fresco, Cattedrale di Santa Maria Assunta, Cappella del Vescovo Costantino Eroli (Cathedral of the Assumption of St. Mary, Chapel of Bishop Costantino Eroli), Spoleto, 1497