Wow, this also make sense
It is true
but isn’t hajin older than him?
Nope!
It isn't like an illegitimate child, but Hajin's father didn't want a second child but Hajin's mom got pregnant with Hajin and yeah smth like that, I don't remember the full details but Hajin isn't really an illegitimate child
i don’t understand why is he wearing an high school uniform then
Well it's cause Hajin and his brother were made to switch places so Hajin brother would be like in higher grade in university compared to Hajin if he hadn't switched places with Hajin. I don't think Hajin is that young to be in highschool so it's def that the older brother was forced to change grades
i actually read somewhere that the white hair dude was the real child of the ceo and the actress and "yoo hajin" was the ceo's illegitimate child. however hajin was the one who looks liked the ceo so he chose him to be his heir.... im not sure if this was really true tho