(I suppose you're talking about Doumeki)
Doumeki's family adopted a girl. The girl fell in love with her brother, so he decided to keep his distance. He became a cop, and then found out that his sister had been raped by their father while he was avoiding her. He beat the shit out of his father and to protect the family reputation didn't mention the rape part and had to go to prison.
When he got out he strated working in construction work, where a guy from a loan company (guess that's the name) saw him and asked him to work for their company because Doumeki's well-built. The company was yakuza so he kinda got dragged into all that. And Nanahara thought they could use him as a bodyguard because they were short on people, Yashiro got interested in him, saw he was impotent, and made him is driver and bodyguard.
There you have it ^^
(but just read it again)
THANK YOU! I will read it again but you've seriously helped me understand it better ヾ(☆▽☆)
I love this Yaoi, its so intense. It is literally worth the wait for the new chapters, they always deliver excellence (≧∀≦) I think i might need to start it again, because i got quite confused at some point. Can anybody explain to me the whole situation with his dad again and also how he got the job as a yakuza bodyguard in the first place? please?