Whoreson's Mansion - Gifted to the most deviant of Novigrad's Big Four, this mansion and grounds located in Oxenfurt are heavily guarded, and trafficked too; the local brothels are consistently sending in additional strumpets for Wiley's insatiable appetites.
Associated quest Edit
It is possible to enter the grounds before the start of the associated quest. This is done by jumping on the railing of a small set of steps near the guarded gate, and from there on to the wall surrounding the mansion. The interior however will be empty with no NPCs to be found and only trivial loot.
The easiest way out again is jumping on the long metal cage next to a wooden shack in the muddy courtyard, then hop onto the shack and over the wall.