For the first several episodes, Brandon poses as Prince Sky, as per the real Sky's wishes to experience life as a normal person. Stella fell in love with him, thinking he was a prince, and Stella was very upset when she found out he was just the squire. Likely, while Stella was certainly upset that he was not a prince, she was more upset that she was lied to. She has forgiven him since, though, and the two now seem very much in love.
