Star Trek: 10 CORE Seven Of Nine Moments
5. Returning To (And Leaving) Unimatrix Zero
While Seven was still part of the Borg Collective, she often visited a place dubbed Unimatrix Zero. It was beyond the reach of the Borg Queen because it was all in Seven's head. Hers, and many other Drones besides. Unimatrix Zero was effectively a computer glitch, created accidentally, serving as a haven for the individual parts of the Drones who shared its existence.
It was something beyond dreaming; a place that both existed and did not. While others could enter, there was no physical realm that hosted it. This was, in some ways, good for all concerned, though it still left it vulnerable to invasion, as the Queen demonstrated once she learned of it.
When she was separated from the Collective by Janeway, Seven didn't visit Unimatrix Zero for over a year. Then, quite suddenly, one of her regeneration cycles took her back inside. Confused at first, she quickly adapted, remembering friends (and more) from the time spent there before. She shed the Borg implants of her waking life, becoming Annika Hansen once again.
She even rekindles a romance with another Drone, Axum. However, once the Queen discovers this realm, the only answer is to destroy it. This act will allow those Drones within to keep their individuality once they awaken, though it will mean that Seven and Axum will likely never see each other again.
It is one of Seven's first brushes with romance since leaving the Collective, something she at first resists, but comes to appreciate. While it would not be the last time she would feel it, you know what they say about your first love...