Here's a(nother) take on this:
How many people, in RL, have committed horrendous acts that they normally would not have, just because a leader told them to? Humanity - and just about every other civilized races used in RPGs - are social creatures. This means that there are times that we (they) will subsume our (their) own personalities to fit into the social fabric. (Anyone remember high school? Been in the military? Joined a club? Etc.....)
All of that means that, yes, leadership and other skills do have the capability to make people do things they may not have originally attended. So, a really good skill check and failed RR do mean that your character will do what the person said. Later you get to deal with the consequences in character, which could lead to a whole (new?) avenue of role-playing. Perhaps he/she will go on a quest to attone.
That said, in RPGs we like to have more control over our characters and this must be taken into consideration. If the PC really doesn't want to do what the NPC commanded, seduced or whatever, then for the sake of game cohesion they should be allowed to do what they want. But I would enforce a penalty to reflect the fact that they are now internally conflicted. (How much of a penalty would be determined by how well they were influenced/failed the RR, but ultimately up to each GM.)
I believe that this is, arguably, the most undeveloped/problematic aspect of RPing.