As the name implies, this involves a royal affair, but it's actually deeper than it may seem. YC would be a princess having an affair with MC, but it's more than just the deflowering of a princess who's over 18 and going behind her father's back. You see, this particular princess is just one of many children in the royal court, and is way younger than most or all of her other brothers and sisters, and she's in no position to inherit the throne, so she has way more free time to herself, and guess what she does with it? That's right, she's having an affair with the unusually young court wizard who teaches her magic in addition to having an affair with her. No, she's not doing it with some guy who looks like Merlin, Gandalf, or Dumbledore, but an unusually talented young man who is only a few years her senior.
It started with a conversation, then a friendship, and now a very close friendship, but he wouldn't be teaching her purely because they're doing it. The "fun" is hardly all they'd be doing, it's just a side thing. I also mentioned that the princess is going behind her father's back, but not her mother's. Not only does the queen know, she helps them hide it and even encourages it, for reasons we'll get to later, if this gets going at all.
The idea here is not to make it mostly "romance", but to make the princess an intelligent woman who can think for herself and wants to learn. She also happens to be attracted to, and possibly in love with her father's court mage. He's needed in court for a few hours a day, but unless there's a specific issue involving magic or a war (which will come up later to add drama), he's left free to do "mysterious magic stuff" as far as the king and the rest of the court are concerned. And he does more than just sneak off with the princess; he actually does things like alchemy, practice spellcasting, take astronomical/astrological charts, and other activities besides the steamy type.
So, anyone interested? Please contact me here or PM me and please be over 18.