It was manhua and a sequel, the story started with one protagonist returning to civilian life after being undercover (in the prequel ig?) And being tortured bc he was found out so he's suffering from PTSD he secretly boxes in an barely legal ring for fun (?) He works in police department and his boss (ml) doesn't like him initially bc he thinks he's not cut for detective work (he doesn't know about his past as an undercover agent) and apparently they used to be childhood best friends but got seperated bc ML's parents were murdered while both of them hid and MC made a run for it inorder to prevent the bad guys from finding ML, basically sacrificing his life (;but only the readers know about this these two hadn't yet connected the dots till the point I had read) please help