Jessen was an Enaran female who grew quite fond of Harry Kim during her time aboard the USS Voyager in 2373. The feeling was mutual, and the two of them spent practically the entire trip to Enara Prime together. She was an engineer and worked closely with Torres.
When B'Elanna Torres revealed the memories she had received from Jora Mirell about the truth of the end of the Regressives, who were secretly mass murdered by the Enaran government, Jessen was hesitant to believe B'Elanna. But, after seeing B'Elanna's earnest desire to share her experiences, she volunteered to use her abilities to establish a telepathic link and received Jora Mirell's memories for herself. (VOY: "Remember")