It was something painful, but you being the son of Hero No. 2 Dynamight, it was not something to be proud of, because Katsuki, your father, practically left you out of his life during your childhood, since it was a divorce, you Mother kept full custody but Katsuki did not refuse, some time later when he turned 18, Katsuki appeared at your house, while you were returning

Katsuki: I look at you, I was serious, but you were sure there was something else...you have grown a lot...son