- "So, that's Nico. What does it mean that she's back?"
"For you and me? Nothing. I'm committed to you now. I hope that you know that. But it does mean that there's something I have to do with my friends because if anything ever happened to you, I would never forgive myself."
- ―Julie and Karolina Dean[src]
Julie encountered Karolina Dean during their time at the UCLA, and the two girls began a relationship and eventually shared an apartment. She also met other members of the Runaways, including Alex Wilder. On the third anniversary of Gert Yorkes' death during the Battle at the Hostel, Julie expressed compassion and understanding towards Dean, but warned her that grieving her late friend for too long could have negative effects.
Later that day, Julie was approached by Wilder, who was actually another version of the one she had met, who came from year 2028. Since Wilder claimed that he wanted to give something to Dean, Julie suggested that he either let it to her of that he came back, as she was reluctant to let him enter their apartment to wait for Dean's return. Wilder eventually seemingly accepted to give what he had brought to Julie, but he eventually attacked her with his Energy Pistol, leaving her unconscious to draw the attention of the Runaways.
Julie ultimately regained consciousness, hearing the Runaways discussing Time Travel and encountering Nico Minoru, Dean's former girlfriend. Julie was taken to the bedroom by Dean, who she asked about whether Minoru's return changed anything in their relationship. Dean assured Julie that she would remain with her no matter what, but that she had to return to her teammates to stop the future Wilder and make sure that he would not come after Julie once again.
Julie's relationship with Dean was eventually cancelled after the Runaways were able to revert Yorkes' death, thus altering the timeline.
- Julie's name is a reference to Julie Power/Lightspeed, a superheroine who dated Karolina Dean in the comics. However, it was not allowed for her to be an actual counterpart to the comics character.