Possible Misunderstandings:
* "Nikki" might be a misspelling of "Nicki": There's a character named Nicki, a human girl who was the daughter of the scientist Dr. Arcee in the Transformers: Animated series.
* "Nova" might refer to a different character: Perhaps you're thinking of a character with a name like "Nova" or a similar-sounding name, like "Nova Prime" from the "Transformers: Cybertron" series.
To give you a more accurate answer, please clarify:
* Which Transformers series are you referring to? (e.g., G1, Animated, Prime, etc.)
* Can you provide more context about the character you're asking about? (e.g., what they looked like, what they did in the story)
Once you provide more information, I can help you figure out who you're thinking of and what happened to them.