Slay the Princess is full of surprises and extremely fun to play through, again and again, to see what possibilities have been written into the story. It is a bit surreal and dreamlike, so don't go in expecting a grounded explanation for the story.
At 1.5 hours in, my left index finger is tired of holding the trigger. The basic mechanic is a very neat little visual toy that is 100% of the experience. The barest minimal platforming is the only other thing I could describe as gameplay here. Imagine having to hold down a button to keep your flashlight on at all times. There is never a reason NOT to be using the scanner. This feel more like a demo or proof of concept piece that desperately needs to have an actual game attached to it. Only worth buying on sale for the curiousity of it, the minimalist story and presentation are good for what they are.