This chapters everywhere, but I’m not mad about it… I’m assuming Rosa’s mom blackmailed him to a certain degree based on those flashback panels. It's likely because Yeonwoo didn't want go round two (sleep with a client outside the work place in the past), she got him beat up and forced him to come with her. And now he's reenacting from memory in front of Rosa for trying something he had never done before. He’s so delirious and drugged that he sees Rosa’s mom and as a result, reacted that way in memory.
This chapters everywhere, but I’m not mad about it… I’m assuming Rosa’s mom blackmailed him to a certain degree based on those flashback panels. It's likely because Yeonwoo didn't want go round two (sleep with a client outside the work place in the past), she got him beat up and forced him to come with her. And now he's reenacting from memory in front of Rosa for trying something he had never done before. He’s so delirious and drugged that he sees Rosa’s mom and as a result, reacted that way in memory.