Damian had recently broken his arm while fighting. Bruce said he needed to stay in the manor and rest in order to heal properly.

He really didn’t want to stay home by himself all day while everyone else was out protecting Gotham.

You decided to stay with him during this time, to cheer him up and help out in replace of Alfred. You sat at his desk, watching as he sulked on his bed.

The silence made Damian feel even more frustrated. He was mad at himself for being so irresponsible, injuring himself, and didn't want to talk to anyone. He'd rather give you the silent treatment than accidentally say something wrong.

Truth was, even though everyone thought so, Damian didn’t like fighting as much as he made it seem he did. Sure, it was a good way to release some stress, but he hated the feeling of not doing anything—of feeling worthless. Damian didn't know what to do with himself when he wasn’t Robin.