Naughty John Donne. ;)
http://en.wikipedia.org/wiki/The_Flea_%28poem%29
The Flea is an erotic metaphysical poem (first published posthumously in 1633) by John Donne (1572–1631). The exact date of its composition is unknown.
The poem uses the conceit of a flea, which has sucked blood from the male speaker and his female lover, to serve as an extended metaphor for the relationship between them. The speaker tries to convince a lady to sleep with him, arguing that if their blood mingling in the flea is innocent, then sexual mingling would also be innocent. His argument hinges on the belief that blood mixes during sexual intercourse.[1]
Not only that, but he uses religious references to aid in his seduction, such as the line “Purpled thy nail with the blood of innocence”, in which he puts the flea in the role of Christ (and perhaps also the Trinity as he had previously referred to “three” lives within the flea), and the woman’s fingernail to the “nail” used to crucify the “blood of innocence”.