How much NTR is this game?
Very little. If you interrupt Evelyn when she's in negotiations with Thaddeus (this is obvious in the game since their portraits on the map screen are side by side when they're negotiating, so it is easy to avoid seeing them together), you discover that she's using all of her assets to sway him. The first time you interrupt them, you see them kissing. if you choose to tell them to stop, then that's it, their involvement ends with kissing and never continues. If you don't interrupt them and look in on them a second or third time, you see them engaging in oral or anal sex.
The game gives you some money every week as long as the negotiations are going well, and that supply of funds stops when you tell them to stop. Otherwise there's no penalty for telling them to stop. The benefits of stopping them are that it makes Evelyn considerably easier to seduce. Since the weekly money is helpful (but not essential) in the early game, i generally avoid stumbling upon the two of them together until I am ready to cut off those funds.
An early scene involves the protagonist having sex with the queen of the fairies, because her vision told her it would prevent a horrible war if she did so. There is a king of the fairies, who does not like this idea at all, but that isn't usually what people mean when they ask about NTR.
