[Kaishaku(介錯)] UFO Princess Valkyrie (円盤皇女ワるきゅーレ) - Vol.07 [2005-10-22]
Sanada first gets possesed by an evil spirit and turns evils, later the spirits passes to Kazuto, and finally to Valkyrie, transforming her into Dark Valkyrie. By the way she kills Kazuto (almost), I hope that's evil enough.
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