Definitely something different to say the least.
I enjoyed how different the moving and shooting system is, it's definitely trying something new for a bullet-hell game. I think it's definitely got potential to it.
There are some issues though:
GAMEPLAY: While i do enjoy the creativity of the movement system, i do not enjoy the difficulty it presents. Due to the fact that big enemies like the cupids or teddy bears have larger health pools, the saw or flamethrower would work more effectively against them, but sometimes (especially due to the issues with character size that i'll get into) it's really difficult to get to use those on those types of enemies due to the damage your character suffers from trying to rotate your guns around.
The controls aren't too bad, and overall i think that the enemies have enough variation to be somewhat entertaining. That being said, the character you play as is really big for the small size given, which makes it hard (especially against the little fast faces) as moving is what allows you to rotate you weapons, and due to that, your character is almost always going to risk running into the edge of the screen quickly, and get slammed by enemies just spawning in, or will end up running into new enemies, just to get the most effective gun, making the mechanics more frustrating than fun.
AUDIO: Please turn down the audio, the sounds are all very high pitched, and the sound is not regulated; while i can turn down my speakers, it's courteous to balance the sound levels to a reasonable level. That being said, i commend you for putting in sound effects and catchy music, it helps set the atmosphere and pace, really well done.
VISUALS: The visuals are nice, albeit quite simple. The heart is seemingly the only animated sprite, and the blood dripping from the screen as well, it's quite cool. I would definitely add in some more sprite animations, weapon animations (the bullets and flames in particular).
I would like to note though, that the stark contrast between your cutesy enemies, and a beating heart is very weird. I don't think it's a bad thing, but because there's no real explanation, it's just strange. I would try to maybe add in a short explanation for it, or try to at the very least match the enemies a bit more with your character, as the contrast is very confusing. Interesting concept though.
GAME IDEAS: I would definitely consider expanding screen size or shrinking the character model a bit: try to add in some levels if you can, and I think your game would benefit a lot from some type of points/skills/weapon upgrades system, to really help get a feeling of progression, and to entice the player to play your game longer. Overall, a neat little idea, a refreshing burst of creativity, and a nice use of 10 minutes of my time. Thanks for the fun!