TwoHandedSword: There's a whorehouse you can frequent, which includes a sheep you could potentially dally with; certain quests can require or allow a sexual encounter as part of their resolution; the game features overt and implied acts of racism (usually against half-orcs); and the violence options can be set to be rather graphic (as in, you kill something, you can see its innards).

However, the closest the game gets to actual nudity is underwear (mind you, walking around in your tighty whities will still get you branded a pervert); and all sexual encounters happen behind a fade-to-black. So if your cousin is at least 12, there's probably nothing that will shock or traumatize him or her. Any younger, and that'd be your call.