Complete Monster/Umineko no Naku Koro Ni


 * And Arc 7 brings a huge surprise... No wonder   has an Heroic BSOD after finding out and   opposes them.
 * arguably comes up as the worst in this case, though.
 * And Eva, who was thought to be the worst monster among the family, due mainly to the events of Arc 3? It turns out it was all a fabrication so that she could paint herself as a Complete Monster just so Ange didn't have to know that  So in the end, Umineko's reigning queen bitch turns out to be willing to allow Ange to hate her just so she doesn't have to know the truth.
 * Lambdadelta could qualify for the trope, since she tried to make the fight between Battler and Beatrice last forever, all to "trap" Bernkastel.
 * Also, it has been implied that she helped Miyo Takano in her conquest of killing Rika and becoming god. This was brought up by an interview with the creator of both visual novels.
 * Black Battler from Ougon Musou Kyoku CROSS is a negative palette swap of regular Battler who lacks the good-guy depths that his real counterpart does, not only talking about killing everyone on Rokkenjima but also suggesting to female characters that he's going to rape them, and he "tastes" male characters. He has a wicked habit of killing anyone he feels like killing, strictly For the Evulz, and laughing about it.
 * Also, it has been implied that she helped Miyo Takano in her conquest of killing Rika and becoming god. This was brought up by an interview with the creator of both visual novels.
 * Black Battler from Ougon Musou Kyoku CROSS is a negative palette swap of regular Battler who lacks the good-guy depths that his real counterpart does, not only talking about killing everyone on Rokkenjima but also suggesting to female characters that he's going to rape them, and he "tastes" male characters. He has a wicked habit of killing anyone he feels like killing, strictly For the Evulz, and laughing about it.