I've just recently started with tree books together :
1) "The complete poems of John Wilmot, Earl of Rochester. Ed. by David M. Vieth."
Some of the juiciest poetic bawdy ever written i english. Rochester lived in the 17th century, 1647-1680, and became one of the favourites in the court of Charles II.
2) Antonio Vignali : La Cazzaria. The book of the prick. Edited and translated by Ian Frederick Moulton.
Vignali's (1500-1559) "La Cazzaria" was published in 1525 and is one of the very first sexually explicit homoerotic philosophical dialogues.
3) James Grantham Turner: Schooling Sex: Libertine Literature and Erotic Education in Italy, France and England 1534-1685.
Turner's book is probably the first full scale history of libertine erotica in the 16th and 17th century. I'm pretty sure you'll get the connection between those three books...