Premise: This game is a parody of Bible Black. You play the game as a demon who possesses a body that is a younger clone of the nurse Kitami (called Envie here); you are a futa. I believe the game centers around the premise that Minase never found the Bible Black, and the story focuses around you and Envie trying to summon a powerful demon. You go around and use spells to uncover secrets at the college, and have lots of hot sex with various characters.
The art is gorgeous. I believe the models are made in Koikatsu, and they look really good. The sex scenes in the newer version are very good, and there are only a few outdated scenes that the developer is working on redoing. The story is good, and you'll be excited to see what happens next. There are a lot of great futanari on female scenes in the game, which is what I like the most, however there are also some male x female scenes and yuri scenes. Your character does know a spell to hide their penis for several scenarios, which allows for these scenes to occur.
Make sure to check the walkthrough that is in the thread OP. Spell casting can be tricky, but the guide is there to tell you what to do.
If you are a futanari fan, or you enjoyed BB, then you should definitely play this game. I am looking forward to seeing where it goes.