A little short, a little too dependent on fake difficulty, and a little clunky.
While you captured a lot of the feel of the original Castlevainia SOTN in your game-play, it didn't handle as well as I would have liked. Meanwhile, it was excellent reminiscent of the opening of it.
Solely on gameplay: The lack of a sprint function (Double tap side, if I remember correctly) made long jumps nigh impossible (And was very frustrating remembering what this was partly based on.)
Solely on content: Add more, add an inventory, and do a full length parody! You obviously got the basic spirit down, but its still a little rough. The only challenging bit of the script would be adding in the more monstrous bosses (Given the theme you are taking, it could get a little offensive,) and who the hell you are going to make the protagonist that comes after the prologue (Although making the Katawa Shoujou protagonist (Hisao???) storm the castle to encounter a snowy bridge and getting asked out (Thus causing his heart attack) would be a hilarious (Funny aneurism) way to take away his overpowered starting gear.)
Keep it going, and hopefully we can see a full length version.