Harry passes Bode in the Ministry of Magic on his way to his hearing. He observes that Bode is "a sallow-skinned wizard with a very mournful face" (7.141). Mr. Weasley comments that Bode is an Unspeakable: he works at the Department of Mysteries. Bode winds up getting Imperius cursed by Voldemort in an effort to get at the prophecy.
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Because the only one who can take a prophecy from the Department of Mysteries is the person for whom the prophecy is meant, Bode is physically incapable of doing what he has been Imperiused to do. So he suffers some kind of magical stroke and winds up in St. Mungo's Hospital. To prevent him from regaining consciousness and explaining what has been done to him, someone (possibly Lucius Malfoy, who has been hanging around the Ministry so much) sends Bode Devil's Snare, a plant that will strangle you to death if it gets you in its grasp. The healers at St. Mungo's think the plant is a Christmas present and place it by his bed. It kills him in the night.