From Halopedia, the Halo wiki
Eifinn Rein was a human who listened to Benjamin Giraud's Hunt the Truth audio journal in 2558. After Giraud's entries revealed long-hidden truths about the Master Chief's backstory, Rein ignored any of the dark implications and sent Giraud an audio email asking for more personal information about the Spartan, such as what his favorite food was. He planned to start a restaurant with a Master Chief theme, with fast food items named after him.
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