"Oh!" Billy said, taking a moment to realize what the heck it was that Tim was talking about. It wasn't that he forgot that Tim was a superhero, it was mostly that Tim just didn't seem like a superhero when he was out of costume. So maybe Billy sort of did forget that his good friend was also a superhero that kind of annoyed him.

"I think I have a backpack here you can stuff your work clothes into if you need to?"