The story takes place 7 years after Majin Buu was destroyed...
Trunks is 15 years old. The shadow of the shy boy who traveled through time and space is still vaguely visible. He entered school a year earlier than Goten and completed the necessary middle school courses ahead of schedule. Now he is taking a leave of absence from school to try to study at home to help manage the company.
At that time, Goten was 14 years old, still smiling innocently and carefree, and started his life in the first grade of junior high school.