My most initial thoughts are, "He is beautiful and his banter with the MC is so cute!"
Your writing flows so well from the lore to the MC’s thoughts to Heimos’ personality and passion. The BGM is so calming at times and positively hair-raising the next, perfectly suiting the atmosphere of the entire VN.
The difference in Heimos’ treatment of you when the MC makes the more "disagreeable" choices is so beautifully cold and adds much more depth to his personality, albeit painfully so, coming from a romancer's perspective.
I love that the options the player chooses for the MC’s emotions and motives persist throughout their stay with Heimos and that they're recurring plot points, instead of just being a fleeting feeling or action in one scene, which adds to the authenticity of your characters and the overall immersiveness of your game. I also love that you’ve sprinkled in little bits and pieces of lore throughout all the different routes instead of simply just putting majority of them in the “best” path to take.
///SPOILER START/// Like Heimos' given name not truly being Heimos ?? The presence of and relationships between the other living gods?? wow ily ///SPOILER END///
I love all the variations of the good endings, even the neutral or bad ones. It all makes perfect sense really, and I love this little world you’ve created for Heimos and the people of Frostdine. Can’t wait to explore more of your Sacrarium universe!