Johan left Kürten at Heidelberg Castle with orders to hold Nina Fortner there until he arrived—and the promise of a hefty payday. When Dr. Tenma showed up, Kürten went for the kill, but Nina intervened and asked Tenma for something to restrain him with. Tenma used the necktie Eva had given him to bind Kürten's hands. With the two of them gone and Kürten helpless, an unseen figure—almost certainly Johan—murdered him.
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