Mad Scientist Precia Testarossa from the Magical Girl Lyrical Nanoha TV series. Her very first scene involves a horrific example of child abuse towards her Dark Magical Girl daughter Fate, or better said, the girl who is a clone of her true daughter, Alicia, whose death sapped away the sanity she once had. It should be mentioned that Fate didn't actually do anything wrong. She did exactly what her mother wanted and Precia still whipped her. She only gets worse from there. In fact, a decent part of the fandom hopes that she survived her fall just so that the heroes can kill her in a suitably epic manner.
Although she is much more sympathetic in the movie, which depicts her Start of Darkness in detail and gives her an Alas, Poor Villain moment. She's more of a Jerkass Woobie in that continuity. YMMV, though.
Precia: Fate, did you just talk back against me? (prepares the whip)
Fate: Oh F***! (gets whipped again)
Or, in the original series, Precia reconsidered if she should've treated Fate like a real daughter. However, in the Abridged Series, it doesn't show her reconsidering. In fact, she calls her a failure before she died.
There is also Quattro from StrikerS, who is such a cruel Smug Snake — much worse than the actual main villain of the season — that you cannot help but hate the guts out of her and stand up and cheer when she finally gets the living crap blasted out of her in a Crowning Moment of Awesome by Nanoha herself. At least Precia was blatantly insane; Quattro is very much sane, she just enjoys hurting others. What would Quattro do with a helpless, terrified, and in very much pain six-year old girl who's crying for her mother? Torture her and tell her that said mother is an idiot, of course! Go. to. hell, Quattro.
Then there's Jail Scaglietti, Quattro's boss and a Mad Scientist far surpassing Precia, who doesn't make any pretenses to having a motive and proved himself to be utterly, disgustingly evil even before he used a six-year-old to power an Artifact of Doom and forced her to attack one of her two mommies, while he gave a brutal Hannibal Lecture to the other. Again, his WTF-pwnage by said second mommy after she recovered from his verbal beatdown was most wonderful to see.
Huckebeins Veyron and Cypha, courtesy of ''Force''. Where do we begin? Veyron is introduced sitting around with dead nuns around him, heavily implying that he killed them. Cypha displays complete ignorance of the many people she's murdered, though she admits that she wouldn't have killed them if she could have helped it, indicating that she was about to go crazy because of her disease, mocks Signum for bringing it up, then nearly kills her while saying the same fate awaits anyone who tries to stop their killings. To be fair, Signum was attacking her with lethal force to begin with before she knew that Cypha was able to regenerate. This might extend to the rest of the family, except Stella, because of her young age (but even she sees nothing wrong with all the killing), but these two are easily the most vile so far.
