The sibling rivalry between Min Jun and Mehmet could be everything weird in this world.
Mehmet used to look up to his elder brother as a child even though their mother were different. But the constant cold attitude of Min Jun stopped little Mehmet from considering the other as brother.
He hated his brother to the extent that he specialises in the skills his brother had been worst. He did not want to be compared by anyone along the lines, 'he is like his brother.' Or people comment about the existence of common interest between them.
When both Mehmet and Min Jun were good in finance, Mehmet refused to work in the field.
Another reason to despise finance for Mehmet was, it was their father's field of expertise.
Min Jun excelled in sports. So Mehmet refused to play those sports.