If you follow the neutral path in Chapter V, then you'll meet two nurses when you start out in Old Vizima. They'll ask you to escort them to the hospital, and, once you've taken them there, they'll head up to the upper floor. Later, after you've completed the quest Under a Fiery Sky, if you return to the hospital and talk to the Nurse from Old Vizima, the pair will sleep with you.

"Fortunately no hedgehogs lurk nearby."