The passage reflects a sense of achievement accompanied by an underlying dissatisfaction. The character completes significant milestones in life, such as obtaining a driver's license, high school diploma, and a university degree, which society often deems necessary for success. However, these accomplishments do not fulfill him, as they fail to address deeper emotional or existential needs.
Despite striving to meet expectations and present tangible achievements, he feels a growing emptiness. The metaphor of presenting "official pieces of paper" like a cat brings dead mice suggests that, although he has met societal standards, he is left feeling hollow and uncertain about his future, as if he has exhausted his potential for new ideas or directions in life.