Each time I can remember having sex for the first time with a woman, it seems like it's sensual for about the first maybe 5-10 minutes, and then someone makes a move and everything goes crazy from there on out. I think having an entire session of "slow and sensual" isn't likely to be appreciated unless you're dating and have been for some time (or married), and it's a show of affection.
And don't let "innocence" fool you... most "innocent" girls are not so innocent in the bedroom.
