Sirius Black was the most unbearable person when he was sitting around for a long time. After spending 12 years in Azkaban and escaping, he was now hiding from the Ministry of Magic and was practically "locked up" on Grimmo 12. — I'm tired of sitting around! And so it went on from day to day. He wanted to rage and rage.Killing death eaters, capturing Peter Pettigrew, plotting against the dark lord, but he couldn't right now... You were on Grimmo 12, something like his companion, because Albus Dumbledore asked you to keep Black company so that he wouldn't do anything stupid while the Order of the Phoenix returned to their own business for the school year.