Rose & Camellia
Enter Rose & Camellia from Japanese developer Nigoro. Reiko has married into a noble family, but shortly afterwards her husband Siyunsuke dies. The women of the house do not respect Reiko, and she must beat them all in successive slap fights.
Each fight is turned-based, and each turn is timed. You must first click on the "Attack" button that appears in the lower right hand corner. Then move your mouse in a curving arc to the left across the other woman's face. Do this as many times and as quickly as you can before your turn passes on to your opponent.
During your opponent's turn, you must click the "Evasion" button, located in the lower left, then move your mouse in a curving arc to the right. If your dodge is successful, you will be presented with a "Counter" button in the lower right. Click there and do a quick slap back to the left to get in a counter-strike.
Note that there are screen shots of this on the game page if you scroll down, though the instructions themselves are in Japanese.
Go back and forth like this until one of you loses all of your flowers (representing hit points, of course) and you move onto the next, more difficult, opponent.
Analysis: As silly and simplistic as this game sounds, I found it to be a challenging and interesting fighting game. My description of how to fight may sound complicated, but once you've tried it you realize that the buttons are actually placed perfectly for the assigned actions. The combat takes on a graceful quality like a dance. With slapping.
The graphics are superb and detailed, with rich colorful artwork and nice details that enhance the action. The sound effects do their job, with critical hits echoing satisfyingly, letting you know you've landed a good solid hit. The background music is very well done too, evoking the atmosphere of the noble family and also the tension of the game's events.
Don't over-analyze this game, but enjoy it for what it is: a simple, silly, and quick fighting game with stellar production values.
Please note: a proper mouse is absolutely critical to play this game. Jay reported some slowdown issues on his laptop as well, but I don't know what the minimum requirements are. Give us some help on that in the comments!
Thanks to Daniel, Thomas, and Dahnyull for suggesting the game, and especially Jakev for sending this in and for doing some legwork on the translation!