Responses
It’s actually his nephew
His brother did It without knowing I think They raised them separate
The son is actually his brother's son. So his twin bro is the one who had sex with their sis. These information are not spoilers. Ch 66, Hue says he couldn't kill the child because his eyes looked like his brother's
http://www.mangago.zone/read-manga/lucia/uu/to_chapter-66/pg-13/
if he has a son doesnt that mean he fucked his sister lmao