Nooo, I want to save the girlfriend!😭 The opening cutscene and voice acting were lovely, and the UI and menus looked very polished (big props for control customization!), but the gameplay definitely needs a bit of work!
The music is nice and the graphics look great, especially on the level backgrounds, but the main character and enemies look a bit zoomed out and thin compared to everything else. The attack animation is cool, but the range is very short, and I think it'd be nice to be able to attack while jumping, or have some way to aim up or do an uppercut attack, as it's very hard to deal with flying (swimming?) enemies without getting hit.
I'm also not sure if the game is supposed to take place underwater, but the movement doesn't feel very "underwater" to me. I think a bit more jump time and lower gravity could help sell the underwater theme better, if that was the intention. I'd also have appreciated a bit more air control while jumping, because landing on the 1-tile wide platforms is very hard (or just make the platforms bigger). When dying or trying to load a save, my character ends up stuck inside a wall.
Still, the demo is nice and the story looks very intriguing, good job!