I got the game recently after the demo was full of win, it's the follow-up to Immaterial and Missing Power. If you need a link,
here (demo download is that blue block in the download list).
Basically it's a one-on-one fighting game but since it uses the cast from a series of bullet hell shmups the fighting isn't limited to melee, all characters have projectile attacks. Have is an understatement even, almost all attacks are done by shooting projectiles of some kind and hand-to-hand combat is mostly a sign of desperation. You can dash through projectiles without being harmed, no idea how that would play out at high-level play.
The most interesting part is the story mode, unlike other fighting games you don't just fight normal battles or have the enemies super-powered in some way, the enemy goes through various stages with many being spell-cards that act pretty much like boss patterns in non-fighting games: The enemy performs some large attack pattern (which can't be reached in normal VS mode though some resemble the super-attacks you can use) where you have to do very specific things to avoid being hit while attacking yourself, instead of rounds you have a limited number of lives and continues to beat the bosses. Since you shoot bullets yourself this kinda resembles a Megaman battle (possibly helped by the developer having made a Touhou megaman clone before).
Marisa seems kinda OP to me with generally fast movements and a very fast laser attack as her forward+strong shot attack that pierces through all bullets and can be used to snipe an enemy every time after he uses some attack, maybe that's just my inexperience speaking though.
Oh and I forgot to mention the weather and card deck systems, the weather changes randomly every so often with effects like "no melee attacks", "hidden cards" or "no flinching or blocking". Each character has a deck of 20 cards that do things like buffs, super-attacks and replacing some special moves with others (or levelling the existing ones). They're gained like super-attack charges in other games, by hitting stuff, blocking, etc and super-attacks will use multiple cards. You can edit your deck (cards are gained by playing with that character) but they're dealt randomly, might be problematic for serious play. You can save player profiles so everyone can customize his decks for each of his characters without affecting other players...