3 needed to calculate an average
Those two series are messed up beyond words and both of them also feature a dose of black humor. In both the female lead (or at least one of them) does whatever she wants and causes others' lives to be miserable in the process and let us not forget the other pitiful misfits present to witness or participate in her actions (when they are not her victims that is). If you somehow enjoyed one, you can't go wrong with the other. On the other hand if you didn't like one, do yourself a favor and stay as far away as you can from the other one.
Both series feature a crazy female inventor highschool girl who causes trouble for others by doing whatever she wants. Both series are crude (though Ni no Maeshii no Tsukaikata is probably more on the squick side). The fact that there is a character who has screw heads on his\hers head in both series also makes one think of one of those series while reading the other. If you liked the type of jokes found in one series, then the other should provide more of the same.