This Star-Thief is not to be confused with either of the other Star-Thieves, Ditmal Pirval or Barry Bauman, even though Bauman’s story, and even his psychic aura, are very similar to hers.
The Star Thief was a princess of an alien race. She was wounded by a laser that went into her brain, and she went into a coma. The laser caused her great pain, and made her hate and fear all small lights.
She had an extremely strong will, as she was accustomed to getting her way as a princess. She was also probably psychic to an unknown degree. The factors combined to let her take advantage of the power of Kubik, who had only recently grown up from his earlier stage as a Cosmic Cube. Cosmic Cubes are able to give their owner whatever wish they desire. The Star-Thief was able to use Kubik’s wish-granting power even though he was in space, not near her.
She used her will to cause all the small lights near her–the night-time stars–to disappear. She took them out of normal space and placed them in a pocket dimension at an alarming rate–if she kept going, all the stars in the universe would soon disappear. However, no one knew that she was doing this–the stars simply disappeared from space without a trace, and their planets froze, killing untold billions.
Some of these stars were sentient, and screamed out to the other stars. One, a nascent star in nebula form named Cloud, heard them and became very fearful. Kubik felt her fear and, being inspired by the heroism of Earth’s superheros, wanted to help. He condensed her to human scale , then sent her to Earth to get help. Unfortunately there were complications and she forgot her mission. Eventually, with the help of the Defenders, she finally remembered, and they all traveled to space to meet Kubik.
Kubik didn’t know that the Star-Thief was using his power to eradicate the stars, and wanted to join in the Defenders’ mission. He took on the form of Captain America and joined them on their quest. With the help of some other aliens, who star had been stolen, Cloud, Kubik, and the Defenders found the Star-Thief’s planet. Her face appeared via psychic projection and threatened them with destruction, but they eventually found her comatose body and convinced her to stop stealing the stars. Kubik then returned the stars to their rightful places.
She eventually recovered from her coma.