Just finished it, really enjoyed it! I'm excited to hear there's a sequel in the works, because this feels like a really solid foundation for a genuine 10/10 eroguro game if they can iterate on it well. Visuals, music (in the moments it played), voice acting, animations and gunplay-feel were all amazing. And the story remained engaging until the end, although I can see why others might struggle to follow it as it can be a bit scant. The only downsides to me were the lack of variety in combat that meant it started to feel a bit samey come the end of the game and the fact that I wasn't a big fan of the design for the xenomorph-esque character (its game over animation is really good though!)
Above all I just hope the sequel adds a bit more H content overall, especially with bosses. I liked the eroguro content, but every boss and "mini"-boss past the centaur woman featured no sex in its game over animation, which was disappointing. If Cyan Brain 2 can fix that, and maybe add multiple animations per enemy and some more fullscreen animations, it could end up being one of my favourites. I basically just want more, which is a good sign that what was there was very fun.