When Heejae was lashing out, we never get to see a clear look at his face until Garam kiss...

When Heejae was lashing out, we never get to see a clear look at his face until Garam kisses him. I think that was intentional it shows how Heejae didn't want anyone to see him at his most vulnerable. Even though he was yelling at Garam and acting out in anger, beneath all of that you could tell he was terrified of Garam finding happiness elsewhere and leaving him.