From Halopedia, the Halo wiki
Instead it somehow ended up in the present (2552) on the computer of Jersey Morelli. The fragment of Melissa didn't know her past, only that she liked to find things. Jersey named her Durga because he believed it suited her personality.
Durga is the only known source of the .wav files or Axons that told much of the I love bees storyline. From 2004 The Operator apparently had a link to the future via Durga, according to the hives.html monologue - indicating that she was spying on Durga, spying on others and that the axon memories are occurring in real time.
As she likes to find things Durga spies on people, people that she picks but for reasons she doesn't understand. She spied on Janissary James for Jersey, and spies on Kamal because a part of her knows that Kamal is her brother. She also spies on Rani Sobeck and Herzog as directed by Melissa but seems to not be aware of it. At James James' funeral, Jersey offers Durga to Jan to assist in apprehending Thin Kinkle and Monster Ann.
Even though she grows a strange, almost familial attachment to Jersey, one thing Durga will not do is transfer Jersey's father, Jason Morelli, to a safer military assignment on Earth. Despite all of her moral and ethical "flexibility", she understands the nature of military duty and will not compromise it, although Jersey wants nothing more than for her to bring Jason home.
However, this may also be because Durga has some knowledge of the Covenant attack force coming to Earth. If this were the case, she would realize that Jason would be safer in the colonies than back on Earth, where much of the population will soon be killed.
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