Bought it, beat it; took a little over an hour. No demo so I'd better describe it:
It's a 2D top down room-to-room dungeon clearing adventure. The main hero is a succubus who's hunting the "unjust" (which her compatriots find funny and odd). "Z" key swings a sword in front of her. Said sword can be upgraded a few times to zany japanese levels so one swing can cover and hit half a room. Of course this leads to the converse of the zany japanese sword where a room has 50+ flying orbs/spits/goop/flares/daggers you have to dodge.
Other items to pick up either by smashing stuff open or killing the lesser mobs are: weapon rune/upgrade, a life meter upgrade, health potions, green gems (currency), continue orbs, keys and a SUPER DUNGEON KEY!!! (that leads to a level boss or a stairwell to the store). The continue orbs are quite worthless since I never used one in the playthrough so had like 50+ of them at game's end. You'll want to save the health pots and spam "A" a few times when you're super low on health, but don't use them to top-off because...
Certain enemies (usually the larger ones) will sometimes become "compliant" when beaten (or explode), and the "X" key will have your little hero jump their bones for a gooey +1 life pip ending. Monsters of this type are slimes, golems, mummies, ghosts/spectres, giant crayfish, swirling squid thing, large slug, probably some others I can't remember. One nice thing is that rooms are saved in the condition left; so if you beat down 3 mummies and they're waiting for a "ride", but you're at full health... leave 'em and come back if you got beat up in the next room. Beware tho, there is a tempting tentacle "trap" plant in the Coast levels that'll suck out your health potions if caught so... don't get caught!
Gameplay is pretty simple and responsive; each room will always have a key somewhere to unlock the next door. Map wise it's fairly linear with only a few side rooms and passages, so no frustrating need to make a map like games of old.
Complaint wise: damn, dem pixels are smallll. Would look great with a larger pixel count and resolution. Sometimes you can get push-trapped into a corner or behind a tree and have to spam chug your health potions until you get free, but only happened once or twice. Beating the head baddy (an evil centaur who had a hole in his torso which I thought he would use to "spear" my hapless succubus hero... but never did

) unlocks the gallery which is just 5-6 pictures. Meh, wanted a sprite animation gallery (with zoooom!). There's no save button/menu, so you have to clear a level and get to the store screen which works as a save point. Continuing from the Main Menu will take you back to the last store you visited (only thing worth buying is the weapon upgrade to get to the super-saayayayayain-Z sword level)
As for the DRM, it operates like DLsites other protected games, so it can be worked around
