lie with

   1. to copulate with

   It has long been assumed that the adult male and female cannot lie in each other's company without copulating, within or outside marriage:

    To tell thee plain, I aim to lie with thee. (Shakespeare, 3 Henry V7 )

   Lie on might be more accurate of the male, but is less used:

    Lie with her! lie on her! (Shakespeare, Othello)

   Lie together implies extramarital copulation:

    Foreign students were positively encouraged to lie together, he said sardonically, so that they didn't go out and pursue the natives. (D. Francis, 1978, writing about Moscow University)

   2. to be buried beside

   Of husband and wife or parent and child:

    I'd like my husband to lie with his son. (Stevens, 1996)