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Nightmare Fuel: .hack
In the second cutscene of .Hack//OUTBREAK; Kite has a brief reunion with Mia, who has been with him for the last two volumes. However, she acts strange, has obscure dialogue ("we can go back and forth freely now," implying that she is going to become one of the Phases entering the real world and wreaking havoc) and makes gestures that imply that all is not well upstairs. And when Kite goes to touch her, she screams at him. Couple this with the accuracy of her English VA, as well as the extremely distorted textures of the current area and you have a scene that should not be watched with the lights out.