- "Go! I'll hold her off!"
- "Zulenna? What —"
- "Her family saved mine. Everything I am dictates I do this. Now Go!"
- Zulenna and Theo 
Her Highness Zulenna Luzhakna, Princess of Holfung-Borzoi, is the descendant of a non-Sparky family who were helped by the Heterodyne Boys in the defense of their lands. According to the Princess, if your family is neither noble nor Sparky, you are not worth her bother.
Zulenna is an expert fencer, suggesting she has been training at the art of swordplay for many years by the time Agatha meets her. Once she discovers Agatha's true ancestry, however, her sense of honor obliges her to use her skills to aid Agatha's escape from Castle Wulfenbach. Unfortunately, instead of merely facing down Von Pinn, she crosses swords with Bangladesh DuPree and comes out much the worse for it — terminally worse.
On discovering her death, Baron Wulfenbach orders her body placed in the cold room in his medical lab, presumably for revivification. One of the Lackya reminds the Baron at this point that the Fifty Families would not permit a royal personage (or more to the point, royal succession) to be "tinkered with" in this manner, but the Baron replies it will be the Princess's choice whether to continue living as a construct or not.
Later, after the timeskip,.