Normally I don't play a lot of dating sims because I find it hard to enjoy them when I don't like the partner choices, but there is a lot of humour in your summary (that nipple warning, haha) so I came in expecting a lot of light-hearted otome humour, and your team fully delivered on that front!
It's extremely polished as a full package: GUI is tailored for the spooky theme, sprite and bg art is clean + special CG for each character route, and quite a lot of effects like the storm at the beginning. It took me by surprise when I found out I could move the camera when a guy's face is zoomed up close. The heroine's portrait is also very expressive with her different face reactions.
I refrain from commenting on the guys because this is too reliant on the player's preferences, nevertheless I tend to always check out all of them for completeness. As for story goes, Jusépe route is the absolute highlight for me. I encountered Fabious before, and his route was short and sweet. Jusépe's was not the type of exposition/revelation I was expecting from this VN, and from that point it entirely hooked me in. I like how each branch brings you something new; may they be locations in the house, lore drop, or character events; it captivates your attention through the entire playthrough with fresh content. Even when I don't want the heroine to make certain choices, I still pick them to see where it leads to due to this.
All in all, this entry is an amazing spin-off to your main game because it really makes me curious to see that one as well, while also being meaty enough for standing on its own as a fun Halloween-themed otome. Had a great experience!