It will work like a mini-game, where you should interact with the girls while in an event. It's simple, very simple, but sometimes it can cost you a bit of boxes (money). Here are the girls:



In order (from the left to the right): Biscoito, Daisy, Agatha and Jane.
Interacting to them will take some hours, so you can't do everything with them all. =]
Why would I spend my precious time talking to these girls?
Well, when one of them likes you, you can take her to your room.

When you wake up (and she's gone), you'll receive a prize. It doesn't worth a box, but it will be show at your profile screen, like a trophy.
Biscoito:
Always happy and love animals, nature and stuff.
Daisy:
She talks, walks and acts like a child, but she's very cleaver. Loves big cities and she's vegetarian.
Agatha:
She is very reserved and shy, so it can complicate things to you. Likes to read books and help others.
Jane:
She's hard... to talk! She can say the whole vocabulary in minutes! And is know in whole city... well, you should know why. Loves eletronic gadgets and stuff.
Note: I didn't tried to copy any girl from the Harvest Moon, although I saw they got similar... =/ Hope there's no problem to you...