Try GSL (GameStoryLog) as a centralized location for reviews and information about AVNs. It is free. Pirating paid content makes the problem even worse. But seriously, Origin Story is 100% worth it. I've got no skin in the game (no pun intended) and it is one of my top games of all time.
No there isn't once there. Its all paywalled or nothing. If I did get a hacked version, they did the creator a favor because NOW I plan to buy it. I'd never expect anyone to buy my game going in blind without trying it out. The creator must have gotten a massive marketing boost somehow to be able to afford to do this. I know it was featured or discussed on adult game review on youtube. Still not enough to make me buy it blind. There are SO many great games out there that do have demos that I feel are on par with this one I could spend my limited money on instead.