Julius meant to keep this meeting, even if he was not so honest or punctual with his other appointments. Even so he loitered outside of the door to Slughorn's office, making the man wait. He wanted to inspire at least a little doubt in the back of his Professor's mind. Julius had found people were so much more agreeable to suggestions when they thought they might not get their own way.
It was incredibly unfair that the terms of their agreement hadn't been laid out for him to begin with. Julius was never so rude towards his friends. He always made sure that his favours were well understood. He swallowed, fighting back his anger. It wouldn't help him in the long run to appear in the room with a face full of thunder and the disposition of a cat who had just had his tail stepped on.
Composing himself, Julius raised his hand and knocked on the door. "It's me, Professor. Can I come in?"