While you interact with the various girls, the main measure of what they think of you is summed up in "appreciation points" (AP). The higher the number of AP a girl has, the better opinion she has of you, and she'll be more willing to do stuff with you. Many girls require a certain amount of AP in order for them to tell you their phone number, tell you if they have a boy friend, etc. Each girl starts out with an initial number of AP depending upon what she thinks about you. You raise a girls AP by talking to the girl, lending them stuff in school, dating them, and though other special situations for each girl. Certain actions, such as refusing to lend a girl something in school will result in a loss of AP. Sound complicated? Well that's just the way girls are...