@Tearsax Then it was lost in the translation, because in the raws he mentions them by name, at least the brother. And it doesn't matter that he was with her since before, because they "broke up", actually he was the one who initiated it. From that point, orange got together with the MC, and he did know it as he met them, when MC was called about the job, and he spoke to the orange. His face wasn't shown, but from the chapters before and after, it's quite obvious, especially with the reaction from orange. So he walked right into it, especially when he decided to mock the MC after they got busted. Sure, it was overboard to an extent, but not undeserved. Bitch should've gotten a punch or two imo.
I guess it would be some unseen third party, because if he was beaten up that much, and it goes to the police, he can't really cover it up in front of his wife either, aside from the blackmail material MC already had. With the authorities involved, there are records of what happened, where it happened, who was there, so he had quite a lot to loose.