This game is excellent for plenty of reasons, top tier. Allow me to get into a few.
First and foremost, it is an RPGM game with good combat. What does this mean? It actually feels like a game instead of mashing AOE spells to see porn. Multiple resource bars are actually utilized effectively, with stamina knocking you down and mp being your final defense. I could get into how later bigger spells become risk reward, the fact that tp skills feel distinctly different from mp ones, how you actually earn/level skills, etc. If you enjoy RPG gameplay, this game delivers.
The difficulty scaling is rather unique in that while you can choose a baseline, the world grows as you defeat bosses. Grinding exp is somewhat pointless after a point because of this on harder difficulties, and you get more out of refining your build and strategies. The loop rewards progressing the game instead of grinding. Different encounters incentivize different strategies. Bosses have a gimmick of sorts, but the gimmick meaningfully affects which strategies are effective. You will hate some, you will like some.
The world map is refreshing in that it's one big interconnected map. You can travel from end to end if you so desired, or fast travel later. There are also dungeons, each with a distinct theme representing their region. While visually the fidelity isn't top class alone for RPGM, the direction feel and design make this a standout. Did I mention that there is an incredible amount of unique assets? Rest assured, every single mob is entirely unique (unless you've played the devs previous games).
The game has a good story. There are twists, there are feels. The writing itself is fun and full of puns. It is not "go defeat the demon king" slop. If you appreciate this I would recommend it. Though it can be a bit wordy at times.
Pornwise, I can't give an unbiased review, I'm a huge fan. It's split between various standing sprites and what the game calls critical scenes. Essentially, you've got a good battle fuck template, and if you meet certain criteria (recollection will hint what these are) you get the full cg scenes. While the scenes don't vary, all of the restraints and battle art vary with the costumes. The costume system also has separate destruction for top and bottom, go crazy. The majority is not direct penetration, but it does exist (I can think of at least eight from memory). As far as total amount of content, I would say that it's above average. Monsters abound, only a few humans to be seen.
TL;DR: Very good game, and a very good porn game. Does not reward a quick fap. You'll get more out of it if you play it as a game before a scene gallery. I've played hundreds of porn games, this is safely in my top three. Absolute classic alongside Taima Miko Yuugi.