I love stories about artificial intelligence, robots, androids etc., something about the idea that artificial intelligence is so close to humans that you can hardly tell them apart attracts me magically. And even if that's not the main story, it also plays a role in Project Passion.
Moreover, it is an action-Sifi-VN with good humour that I would place somewhere between "The Hitchhiker's Guide to the Galaxy" and "Marvel".
The characters are unique, have their own motivations and secrets. Heartrending moments alternate with shameless irony. The MC is a mixture of hero and naïve, carefree good-for-nothing, definitely likeable but with many flaws. And that, for me, is also what makes him so charming. I much prefer that to the perfect hero who takes the ladies by storm.
Project: Passion convinces me both as a comedy and as a serious story about personal growth and true friendship. But it's also a good AVN with erotic scenes and a Marvelesque sifi-comedy.
On the technical side, I don't know any developer who does such a great job of incorporating non-sexual animations into the flow of their stories as Classy Lemon does. I already noticed this in After the Inferno, but in Project: Passion it's even more striking.