Maybe madman combo?
no it's a yaoi and the ceo or mafia leader is so inlove with him and don't have any plan to let him go and even his prosecutor brother is inlove with the uke
madman combo is a yaoi you should check it out I am pretty sure you are talking about this the uke has pink hair and the hot seme has black hair and the prosecutor brother you mentioned has brown hair
i found it already it's Assorted Wildness
so i read this manwha last month
The story is her sister is nowhere to be found and the Ceo or something take him and look him up because her sister is the mistress of the guy brother in law the last update i remember was he runaway with his ex to ho to busan to find his sister