Your mileage may vary on this, but in The Fear Hole Professor Melancholly gets this in Episode 7 when he murders the adorable childlike Antagonizer in cold blood. What really sinks this past the horizon is that Antagonizer was telling Melancholly that he loved him.
RWBY: Adam turns out to have a lot of issues with Blake for abandoning him during the Black Trailer. He tells Blake he intends to destroy everything she ever loved for having the temerity to walk away from him. He stabs her to provoke Yang, then slices Yang's arm off. When Blake tries to shield Yang's body with her own, Adam victim-blames by asking her why she has to hurt him, then decapitates her. It turns out to be one of Blake's shadow clones to give her time to flee with Yang, but the illusion fooled Adam and he didn't hesitate to decapitate her.