John watched them leave, and than turned to Sherlock. "Are they... [i]dating[/i]?" He looked back at the doors. "Greg seems a bit too... nice to be dating Mycroft." He looked at Sherlock hesitantly. "No offense, though. I know he's your brother and all, he just seems very... demanding. And intimidating" He scratched the back of his head, looking a bit nervous. God forbid he insult Sherlock when he's just become his friend. He'd just become friends with him, and learning things about him, he didn't want to make an enemy. 
For some reason, John wanted to learn about Sherlock, and his cool powers. He also wanted to just [i]be his friend[/i], because judging from the other two it looked like for whatever reason he didn't have any. It kind of made John sad. He wondered if Sherlock was bullied in his hometown, or wherever he lived when he wasn't at Hogwarts. Wizarding students had to go to school for those 11 years, didn't they? There was no way that school just started at age 11. How did they learn math or how to read or any of the boring, 'muggle' stuff?