Ningyou no Yakata

>Story
Being an adaptation of a VN, there's a significant (for a hentai) focus on a story here. Sex scenes contribute to a coherent narrative built around the titular dollhouse. Unfortunately, attempts at storytelling fall flat due to extreme pacing issues (whole plot is summarized in 2-3 minutes right before the anime ends), while whole first episode barely touches upon it.

>Art
It's very uneven - some of the sex scenes are barely animated and are more akin to a gif made by beginner artist, but others reach the average hentai quality level. Character designs are rather generic, but there's nothing particularly bad about them. The backgrounds are ... devoid of details which is kind of jarring because this very expensive mansion shouldn't look as if it was filled with free stock textures.

>Sound
Completely forgettable, and either way, most of the sounds here is either slurping or shouting in pain, so there's not much space to do anything unique here.

>Character
All but two characters are walking paper cutouts. Due to aforementioned pacing issues, the two actual characters don't get enough screentime to showcase them as people with goals and motivations for doing things until last few minutes of the anime.

>Enjoyment
Having the dollhouse be an element of wider story instead of merely excuse to make characters have sex is probably the only good thing about this anime. Hovewer, story-related issues make it all in vain. Playing the original VN surely is the superior option.