I don't really know how to explain this but it definitely reminds me of the Marshmallow test. http://www.theatlantic.com/health/archive/2014/09/what-the-marshmallow-test-really-teaches-about-self-control/380673/

I guess fulfillment is a higher state of pleasure. With a person, pleasure is a feeling when someone's need is satisfied. They are the most simple needs. If you have ever heard of Maslow, these needs will be categorised into basic needs (including physiological and safety needs). Fulfillment, however, is a state when the next three level of needs are satisfied. They are love, selfesteem and self-actualization needs.

So true =)) happened to me all the time lol

I get tired every morning after waking up. I guess in the end of the day I could fulfill something.