Discussion YMMV / TheTestamentOfSisterNewDevil

I think Zolgia deserves his own Complete Monster entry. Here's a write-up:

• Complete Monster: From the moment Zolgia is introduced, every single action and decision he makes only serves to prove how utterly despicable and irredeemable he is. Offscreen, he murdered Mio's parents and locked Maria's mother in a hidden cell to keep as a hostage for Maria's compliance. It's unlikely that either woman would be safe even if they complied with his wishes, however, because Zolgia's secondary aim (after betraying the other demons and Take Over the World) is to brainwash each and every beautiful woman he sees and make them his permanent Sex Slaves. But he's so impatient to get started on that task that he first attempts to just plain old rape his captives right then and there. As his former minion, even a succubus like Maria was forced to lie to him about her sexier Older Alter Ego to deter him from raping her. In addition to regular rape, Zolgia makes use of the mental type as well. When Basara is taken captive, Zolgia places him into a Lotus-type dream where every Basara is having sex with every woman he loves, all in an attempt to break his will. This is on top of the fact that he created his assistant Zest to be not just another Sex Slave, but one that lets him rape other women by proxy. And he still treated her abusively, keeping several copies of her on standby to replace the old one(s) once they displeased him. When giving Maria a final ultimatum, he preemptively kills her mother (or so he thinks) before Maria even answers because he correctly suspects that she'll disobey. In the off chance that he ended up defeated (he does), Zolgia left a final trump card: his "castle" was actually one of the most dangerous beasts of the Demon World kept sleeping and disguised by magic. His defeat causes the beast to wake up with an unquenchable thirst for living creatures. If left unchecked, it would have self-replicated enough to destroy the entire human world. Zolgia gloats that this was done explicitly so that if he didn't win he'd destroy the world out of spite. After that plan fails and he's taken captive and tortured by Lars, he is still scheming to take the next person he sees as a mind slave...only to discover that said person is Basara. His final moments are pitiful pleas for his life, attempting to bargain with Basara to be spared, despite showing no mercy toward anyone himself. After he's dead, absolutely no one—not even Zest or any of his fellow demons—regret his passing.