Alrighty… Emotion
For this, I based my systems off of the two factor theory of emotion and the model for emotions in kismet
Now, this system is only the model for how emotions are produced and how we remember them, not how they effect behavior.
The first part, which relates to things that directly effect our cat-girl, is
Y=C*X
where C= a positive or negative number that represents the cat-girl's analysis of the situation and the context. C=B+W+N+O+M Where B is the effect the event had on the cat-girl's body, W is the well-being of the cat-girl, N is how close the cat-girl's identity is perceived to be to the cat-girl norm during and because of the event, O is how the cat-girl perceives others are effected by the event, and M is how much the event moves the cat-girl towards her goal. All of these numbers can be positive or negative, where positive means better/good, and negative means bad/worse.
X=a positive number which represents a unit of hormone, which is triggered by certain event and stimuli. A hormone can mean multiple things, for example, being touched can result in, say alpha hormone, being produced. If the calculated context of C is greater than 0, then that touch will be a positive emotion, and recorded as a positive memory, if C is less than 0, then that touch will be perceived as a negative emotion. The amount of hormone is directly related to the intensity and nature of the event which triggers it.
Y is the emotion, or memory of the emotion, calculated here as positive or negative units of hormone-based emotions.
When it comes to events that do not directly relate to the cat-girl, her emotions are represented by the equation Y=N+E+B+S
Here, N is novelty, E is empathy, B is beauty, and S is significance. Y, in this case, is represented in positive or negative units of abstract based emotions.
If an event both directly and indirectly effects the cat-girl, then both equations are used, and the two Y's are averaged together.
Memories which have high amounts of Y(emotions), negative or positive, are easier to retrieve.