Shimobashira Workshop did well with Ambrosia but it's not their best work, which goes to Magical Girl Celesphonia, and most of the issues present here (that ding it to a 4/5) were cleaned up for Celesphonia. Still, it's worth a play.
TL;DR
Ambrosia is an RPGM-H title where the main character, a religious girl, is slowly subjected to corruption. The gameplay and dialogue mostly respect your time and the game will keep H-events and H-scenes prevalent enough to keep you entertained.
Player Choice
Shimobara Workshop is great at giving the player freedom of choice in how the main character is corrupted. However, Ambrosia suffers a bit from difficulty being too easy at times; while it's nice to give the player clear paths, you pretty much have to choose to slow down or corrupt the MC because you likely won't be struggling with combat or choices.
Still, I like the option of keeping her pure or mostly pure or going in on corruption. Situations the MC finds herself in have good build-up and there's a lot of variety in H-events and H-scenes.
Content and Gameplay
The story is passable for what it's worth. It's close-to-mimic, or was mimicked, to their most recent game (as of this review) Enishia and the Binding Brand. The devs seem to consistently enjoy the religious-to-corruption stuff.
Combat and other gameplay is straight RPG-M. It resolves relatively fast, and you will get very strong at a quick pace, so slow yourself with activities if you want a more "natural" move to H-scenes.
H-Details
H-content is really good though lacks animation at times. Shimobashira has consistency along their game titles and I think it works fine, though once again, Celesphonia is the true best at it in my opinion.
Conclusion
Overall a definite "recommend", but consider Celesphonia as being the more refined of the two.
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