I've tested this game on 2 different machines. The first one is a standard gaming PC with RX 570. But the second machine is a Lenovo G500 with built-in GPU (Intel) and experienced heavy frame rate drops, hobble around 15fps. I don't think this game is that hardware demanding for its size. Probably it's not fully optimized because it still in “Early Access” stage. Looking forward to the future updates.

The Itch version is less optimised than the Patreon version (v0.17) definitely. The game does demand more system power than a standard VN because of the massive, complex art pieces for the castle screen, but we have made improvements to minimise those demands over time. The most recent version runs well on my Surface Go 2, which I use for additional testing.

I see, thank you for answering my question.