Diabolus: Kikoku can't decide what it wants to be - porn or plot driven, and fails miserably at both, but it's still highly recommended, if only for the interesting product it could've been.
The whole story centers around three characters, an attractive "bad guy" and two girls who try to make him good. There are no other nameable characters but there are some brief sex scenes of the guy with other girls.
The show should've chosen its path - either be a plain common hentai, make the guy the protagonist and show his encounters with other girls. Or take the story path, flesh out the girls more,
lower the sex scene count but make each of them more substantial. I obviously prefer the latter.
As the ova is now, the sex scenes doesn't excite to their fullest, partly because they feel overly repetitive, and as there are only three main characters the dialog scenes of this anime are more intriguing then the sex ones.
The character design itself hints for something higher than hentai, mainly by the attractive main guy - a unique representation for a male lead in anime, but also for the story's heroin, which has more personality than the common objectified hentai girl.
To sum it up I think there's a real lack of female representation and female orientated hentai. This title felt like something that could've been that for the main guy's design and some of the main girl's conflicts but instead the show tries to be common hentai and that just made a fearful and forgetful creation.
Hentai disappoints once again!