Though Jenny has yet to make an actual psychical appearance in the series, she was portrayed in Nagi's flashback as an adult woman who had brownish-blonde hair and blue eyes. Despite her adult-like appearance, she was said to be 4 years old at the time.
Jenny is first mentioned in Nagi's flashback, where she accompanied her as they roamed the lands of Africa. After having found an abandoned white tiger, Nagi asks Jenny what they found to which the latter insists that it was a "cat" as there are no tigers in Africa. Afterwards, Jenny points out to her that the "cat" didn't have much time left as it was surrounded by a bunch of hungry animals. Seeing that the "cat" was in danger, Nagi urges Jenny to use her rifle to help, but Jenny tells her it was impossible as she then reveals to her that her rifle was nothing more than a novelty lighter that she had bought earlier. Realizing that they too where in danger, Nagi quickly scoops up the "cat" in her arms and runs away from the pursuing animals with Jenny. After having been saved by Isumi, Jenny reveals to Nagi that the "cat" had been wandering on it's own after it's mother had passed away long ago. Nagi asks her how she knew, to which Jenny tells her that she had used her "special ninja skill" to understand his voice, leaving Nagi puzzled on why she didn't use her "special ninja skill" to defeat the hungry animals earlier.