Well I've finished the demo, got to say, it looks really promising and I am glad to see more people like me still like the classic gameplay format, tho this is mostly a metroidvania, what I like the most is the graphics and the silly humor the game has. Unfortunately the demo is too short and, it's quite weird, because I saw footage by AlphaBetaGamer and he confronted a Dracula-like boss, this is not present in this demo because whenever I go either east or west it tells me the demo is finished, so I guess that has been removed, hopefully I will get a more complete demo soon and I HOPE.
I saw that you want to get Yuzo Koshiro in, that'd benefit the game because the music as is now it just... exists, it's not offensive or bad, but it's kinda boring so I was jamming with some Castlevania II and III tunes and honestly that improves gameplay experience, good music elevates a good game into a great game, different tunes for different areas would help too.
Otherwise it looks very promising and I am looking forward for what you have to offer. Cheers!