Actually his sister helped a lot, ever since they were kids, and her situation wasn't much better.
Their dad looks really old fashioned and thus obviously planned to get his only son inherit everything while throwin his only daughter in a marriage of convenience.
Doyhuk was treated like a freak then a monster all his life yet his sister was the only one who stayed by his side, looked after him and cared for him.
Maybe not in the sweetest rainbow and glitter way, but in a very realistic way.
and looking back after the story's finished, she absolutely did the best for everyone.
She definitely could have used better words with him. Even if she was "helping" him, she still used and manipulated him. She wanted the company for herself and used his mental issues to stay above him. She's not a good sister, far from it. She could have done better. Both Seme and Uke deserve better people in their lives.
ヽ(`Д´)ﾉ I don't like his sister at all..this is just my opinion but It was her fault she wanted the highest position so she took it by fkng with his mind like this fkng bi@# fuck with his mind thats why his mental health was a mess (╬￣皿￣)凸 plus his dad was the worst too. (￣ε(#￣)Σ She deserve to be smack really hard and why didn't he use his power on her that wouldbe satisfactory for me.. I'm not satisfied with him taking that job ┑(￣Д ￣)┍ ( i won't spoil much ) yeah of course they are happy together and everything but damn they deserve much better but whatever.