Interesting demo! The main character model was really cool and well-animated, and I'd love to play a full action RPG with her. However, she didn't really feel like she was part of the same world as everything else in the game.
Combat felt super slidey and not very impactful. For one, the animation showed the character standing in place while attacking, yet every attack sent you lunging forward, to the point I think attacking was the fastest means of movement. The "Serious Sam-lite" horde gameplay is a neat concept, but kinda held back by the enemies very obviously spawning above you (and lagging the game). It also didn't seem like the basic traffic cone enemies were capable of damaging me at all.
I'm almost sure the cars around the starting room weren't there when I first loaded into the game, and only showed up after dying once. It was awkward to interact with the levers due to lacking a visual on/off state, and I ended up accidentally closing the door back a few times.
The escalating "ping pong" mechanic of the boss was a cool touch, though not very well-communicated to the player (I basically guessed that was the objective after several minutes of getting nowhere against the boss), and made harder by the aforementioned attack slide forcing me to back up after every successful hit. In general, sliding off the arena was by far the biggest threat of the boss fight and the entire game. The shopkeeper was cute, though!
Overall, the gameplay definitely needs a lot of polish, but the protagonist looks awesome. Nice job!