You might find this earlier answer by /u/46n2arejustaheadofme helpful. To quote this user:

From a HISTORICAL perspective, kissing is mentioned in writing about 5,000 years ago, in Sumerian poetry: (Kramer, Samuel Noah (1981). History Begins at Sumer (3rd revised. ed.). Philadelphia: University of Pennsylvania Press., http://etcsl.orinst.ox.ac.uk/cgi-bin/etcsl.cgi?text=t.4.08.04#[1] )

Later examples from Egypt also mention kissing, and are fairly specific: http://www.love-poetry-of-the-world.com/Egyptian-Love-Poetry-Poem2.html[2] , http://themagentahornet.com/ancient-poetry1.html[3]