Artuhr is in upendo with Guinevere. But they can't be together because the relationship between a prince and a servant wouldn't be allowed kwa the king. their upendo has no chance, Gwen knows that she can't be with him until he becomes king.
The scene in this week's episode reminded me of this. It's not the whole program, only the important parts (and kwa "important" I mean "the parts Bradley's in")