They can be handy when trying influence npc's, but mostly otherwise prowess skill is not used PC vs PC situation but any effects created whit carnal arts work on PC. It is up to PC then how he or she reacts to other PC's actions (whit carnal arts or no).<br/><br/>Also influncing npc can be possible but I think if we start heavily use Prowess skill the scenes ar eless fun in my opinion :P. So occassional use and I sometimes may ask prowess check incase examply seducing a npc but not neccesary at all rest sex scene (if you do not cross a serious fret).