I enjoyed the game as it is now. I prefer the original art style over the replacement, but the dev is just trying to continue the project with the original artist out of the picture. It happens. Unless your pockets are deep, it's difficult to hire professional artists who will mimic another artists style. On a big title with an art team it's easier to absorb the loss of an artist, but on an independent porn game with art on demand as the story advances it's nearly impossible.
But here's what really has me worried: The game, in what most of us would refer to as beta or early access, is not listed as such. It feels rushed to finish the storyline, and we have an ending, but it seems clear the dev intended more for this game. It's on sale on Steam now, 20% off, putting it at about $8 American, and is also not listed there as early access. When a game rushes to sale so soon after release, it telegraphs that the dev is just trying to get what they can out of as soon as possible and move on. It's sad, because I would have loved to see more of this story and its possible branches.