First, a big thanks to Bible Black Ren'Py for a 5/5 port of this game to a platform that's easier to pick up.
Like many others here, Bible Black was one of the first hentai I ever discovered as a teen, and I love that the illustrations and sexual events in this game feel true to the original. It appeals to my sense of nostalgia and even has a few famous scenes from the hentai while still diverting enough from the original story that I don't know what's going to happen next.
My problem with this game seems to be fairly common in Japanese eroges: pacing and the illusion of choice. There are thousands of words of filler/slice-of-life beats in this story that don't move the story forward or effectively contribute to character development. To spice up this filler, the game will periodically give you two choices--but they don't mean anything.
Some of the choices will straight up railroad you like, "You try to do choice B, but are pushed into Choice A instead" while others simply change the next 2-3 slides but have no impact on the rest of the story. This storytelling device gives the game the appearance of being more interactive than it actually is, but left me frustrated when I looked back and realized how much time I wasted reading filler text while sitting on a stock image of a school or a house.
Overall, I give this game 4/5 as a fan of the original IP. If you're not a Bible Black fan, or dislike the aforementioned style of storytelling, you may find it less enjoyable.