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In March of 2556, an industrial accident at the Oros Trading Company headquarters on Mars resulted in the death of Anarosa Carmelo, a brilliant scientist whose mind had been sought after by ONI to create a smart AI program. Having failed to recruit her in life, ONI quickly dispatched agent Prauss and his AI colleague Leo on an emergency run to obtain consent agreement from Anarosa's brother and last living relative, Michael Carmelo. On the way to Carmelo's house, Prauss sped through traffic in his unmarked vehicle while Leo provided him with a breakdown of Anarosa's historical records. When they arrived the man's home address on 7735 Killingham Street, Prauss spoke with Michael on his porch doorstep about ONI's offer to use his sister's passing as an opportunity to create a new smart AI. After Prauss and Leo explained the importance of AIs and how they were made, Michael broke his silence by telling agent Prauss to 'Go to hell' and then closed his door. Returning to their vehicle, Prauss reluctantly prepared to call off the whole operation. However, Leo then alerted him of Michael Carmelo's oncoming approach toward their car. As Prauss lowered his car's window to extend an apology, Michael stopped him and asked to speak alone with Leo instead.
While the two conversed inside Carmelo's home, Prauss monitored their discussions from his car. When Michael asked Leo about himself and smart AIs, Leo revealed that they were not permitted to know about their donors and that they were closely monitored by ONI. Prauss listened in as Leo managed to console Michael by revealing that he was indeed curious about who his own donor was. Leo further explained having parts of memories which did not belong to him and that he thought his donor may have had a child. He told Michael that he chose not to think about his donor as it could drive an AI mad. Leo then shared that while he did not know who exactly he was, he believed that the chance to help others after one's passing was a great opportunity, one that he felt Anarosa and Michael would want to take up. When Michael provided his consent, Leo confirmed Anarosa's pickup order and rejoined agent Prauss, who expressed his admiration at Leo's success. Leo told Prauss that they had to secure Anarosa, as her creation was vital for the scientific work needed at an important UNSC research outpost. After they drove off and stopped in a parking facility, Prauss hesitantly turned to Leo and asked if he had been sincere with Michael about having residual memories, or if he just told him what he wanted to hear. Leo took a moment to reply and claimed it was the latter, stating that he learned from the best of Prauss' ability.
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