
SPOILER BELOW.... READ AT YOUR OWN RISK
actually in the novel, Heewoon's brother&mother face Kangwoo's wrath
After this event, Heewoon live permanently with Kangwoo... and he obey Kangwoo in anything, basically if Kangwoo say go to east Heewoon won't go to west like he almost literally isolated Heewoon from basically interacting/functioning in society, Heewoon wasn't allowed to interact with anyone either from his uni/workplace unless Kangwoo allowed him to... but then again Heewoon felt that Kangwoo's control over him was actually his safe haven so I couldn't say much...
Kangwoo also got rid of the loanshark like no trace left literally, succeed his grandfather's company/workforce, took care of Heewoon's useless brother&mother not killing them but more like got restraining order on them but in illegal sense without Heewoon's knowing
Heewoon's mother&brother couldn't get in touch with Heewoon unless Heewoon's the one who reached out to them first or if they got Kangwoo's permission to do so, if I'm not remembering incorrectly I think he broke Heewoon's brother's leg or something or did he sent this pair of family overseas(?) not sure... correct me if I'm wrong cuz it's been long ago since I finish reading the novel
And at the end of the story after he become the next Chairman/CEO I think Kangwoo got his grandfather/family permission (more like letting them know forcefully without expecting their consents) that he wouldn't get married and letting them know that he only recognize Heewoon as his partner/lover/possession and they don't have a say in his private life whatsoever... then Heewoon&Kangwoo live happily after after
Heewon literally got caught between a rock and a hard place, i dunno about you guys, but his family's still shit, especially that spineless mom, still playing favorites till the bitter end, he's better off with that rich whack job than be a doormat to his stupid brother and spineless mother for the rest of his life, he did everything for them, especially for his mom, but I don't even think his mom ever loved him that much to begin with, cuz when the brother came home, the switch up was crazy af, literally forgot Heewon existed, and kept making excuses for that trash of a brother be fr