Here's some food for thought...
I think you're going to have to think about how this NPC perceives what I call the Now. The Now is what is happening in real time - for example, I am typing this in, what is for me, the Now. It is what I am currently doing.
So let's look at an example of this. You, Arravis, are driving down busy highway at high noon on one of the hottest days of the year. In your trunk are gallons and gallons of water you are delivering to a homeless shelter. You know for a fact that this shelter could really use this water, as they've just been told that their water supply through the city is tainted and can't be used for drinking for the next few days. Its quite possible people might go thirsty for the next few days if you don't bring them their water, and that might mean dehydration and death for the less healthy.
Depressed yet? It gets worse...
On the way to the shelter, you run across a wreck where one of the cars is on fire. A person flags you down and tells you that one person is badly hurt in the burning car, and they can't get her out. If someone doesn';t do something soon, she could be burned or even die before the fire trucks get to the seen.
Here's the hard part: do you use the water in the trunk to put out the car fire and rescue the trapped woman, or do you hold on to the water and give it to the shelter? Both will save lives, and both are good acts - but the choice between them depends entirely on how the NPC views the importance of doing good deeds in the Now.
When you figure out what the NPC will do, let us know - I'd be interested in knowing!