I love how simple this is. Like a couple of people have already said, it's a bit easy to score points when most of the time you can let your girlfriend run free with little risk of getting rained on. That could be fixed a couple of ways (probably combining some of these):
- Make her change direction randomly
- Ramp up the raindrop frequency with the number of points scored
- Only count raindrops that are going to hit your girlfriend
The game has a great vibe though. Nice to see something non-violent (not that I'm really against that) with a happy tune and cute graphics.