Just a question how do I get the 3rd power ?
Hey, thanks for giving the game a try!
So the way progression works is you have to see a number of scenes and have completed certain 'key' scenes.
If you talk to the doll, she'll give you hints towards which scenes need to be done.
To get the option to buy the 3rd power, which I believe is lust, you need to have done the following:
Spy on Mom in bath (speak to her in the evening to start this one).
Spy on the older sister in the shower (speak to her outside in the morning to start this one).
Play a prank on the other sister (go to her wardrobe at night and find a way to shrink her clothes. A bit of a hint, it involves a washing machine).
Hope that helps, but happy to give more help if you're still stuck :)
The game does become a bit more open ended once you get a few more powers.