While James was pondering what to do about Lily Evans, Sirius was brooding in his room in Grimmauld Place. The holiday had been even worse than he had anticipated. In a rare moment of cool headedness, he had decided before returning to his parent's house that he would avoid trouble this summer. He usually enjoyed riling his parents up, but facing their wrath was painful and exhausting. The little fun he got out of seeing his mother and father lose their tempers was not worth it. Not that they need extra provocation to have a go at him. After all, he was a Gryffindor and not directly supportive of Muggle persecution, both traits highly frowned upon in his family. Sirius had lost count of the number of times he had been called a blood traitor and a disappointment to the family a long time ago. He would like to say that his family's opinion of him did not bother him, but he knew deep down in his heart that it was not true. After all, he did a lot of things to intentionally piss them off. The first days of the summer had been quiet enough: He had stayed out of his mother's way and his father had been very busy working in the Ministry. However, tonight at dinner, things had taken a turn for the worse. His father had clearly told him that he expected more of Sirius in the next year. He had stressed that Sirius's frequent detentions and trouble at school were an embarrassment for the family and that they had to stop if he ever wanted to inherit the family fortune. Also, he noted that Sirius's marks could do with some improvements and that the company he kept at school was questionable. Sirius had to fight back a grin as his father described the bad influence that James supposedly was having on him. If only his father knew that James was usually the one keeping him in line. But of course his father worried about the Muggle friendliness of the Potter's poisoning his son's mind. While it was true that James had influenced Sirius in these topics, his main resistance to his parent's ideas came from simple defiance.Hence, their worries about James corrupting their son were unfounded.
However, his father's demands had not stopped there. He had insisted that Sirius had to do something big to make up for his past failures. So, he had to prove his loyalties to the family and to their ideas so that no doubts remained. Sirius had known in this moment that whatever his father had in mind would be horrible. His father had explained that the strong believe in the superiority of pure-bloods and the desire to keep the line pure were the two pillars on which the house of Black had been erected so many years ago. Sirius had heard all this before and had strongly rejected these two principles many times in this past. His father had insisted that most of the current Wizarding World had lost the old ways and that only one true force of proper pure-blood behaviour remained: Lord Voldemort. Therefore, Sirius would join his Death Eaters and thereby proving his loyalty to the cause and making the world a better place. Sirius remembered the absolute silence following this father's statement. His mother had sat at her husband's side and had looked at Sirius expectantly, eagerly looking for any sign of defiance so that she could berate him as she had done so often in the past. Sirius had been in shock, a part of him had known what was coming, but he still had trouble believing that his father would try to force this on him. It was a bold move even for a Black. However, for once in his life, Sirius had kept his mouth shut and had reacted coolly and stoically like a pure-blood had to react in his father's eyes. He had told his father that it was an interesting idea and that he had to think about this suggestion for a while. To his surprise, his father had accepted that without questioning and had given him a week to ponder his suggestion. If he joined Voldemort, all would be forgiven and he would have showed everyone that he was the true heir to the glorious house of Black.
If he did not change the Death Eaters, though, he would no longer be part of the family and would be disowned. He would have to leave the house and never come back.
Sirius had simply said that he understood the terms and had asked for permission to leave the table. His father had let him go wordlessly and Sirius had snuck up to his room. That had been an hour ago and Sirius had mulled his current situation over continuously since then. Deep down, he knew that he could not join the Death Eaters. He would have to leave his family behind and start over. He had thought about leaving his family countless times in his life, but now he was strangely hesitant to severe the ties for good. He was strangely sad even though he had never gotten along with them in the past. Maybe he had overestimated his indifference to his family's opinions. Nevertheless, he would have to make a decision soon, dragging his feet would accomplish nothing. Sighing, Sirius stood up from his bed and walked over to his still packed school trunk. He had so far not been able to summon the energy to unpack the bloody thing. He opened it up and rummaged around in it for a moment, before finding what he was looking for: The half empty bottle of Firewhiskey he kept in their in case of an emergency. He went back to bed, cracked it open and took a deep swallow. The liquid burned his throat, but also restored some of his energy. Somehow, his life always seemed to be so much clearer with a bottle of Firewhiskey in his hand. Sirius took another swallow and put the bottle down. It would not be a good idea to get drunk out of his mind right now. However, he knew now what he must do, frankly, he never had a choice. If his father wanted to him to choose between joining Voldemort and leaving the family, then Sirius would of course choose the latter. It was a surprisingly painful cut, but it had to be done.
Now, he would have to get out of this house. He would try to sneak out without telling his parents his decision. It was better this way. If he told them face to face, things would get ugly very fast and he would be lucky to escape the house with all of his body parts intact. After all, he would be considered an enemy of the family then and the Black family had always dealt ruthlessly with their enemies. So, he would grab his things and disappear into the night. His parents would know his decision as soon as they discovered that he was gone. By then, he would hopefully be far away. Sirius would go to the Potter's of course. He knew that James would not mind and while he loathed to bother his friend's parents, he was sure that they would let him stay at their house no questions asked. He would use the Knight Bus to get there as he was too young to Apparate. Energized, Sirus opened his trunk again. Everything he really needed was in there. His room in Grimmauld Place was mostly devoid of any personal items. He had plastered a Gryffindor banner on the wall as well was a poster of a Muggle motorbike, mainly to annoy his parent, but otherwise the room only held some of his more formal clothing. Therefore, he would not need much time to pack. During the next fifteen minutes, Sirius ruffled through his room and threw what few items he wanted to keep in this trunk. As it was becoming quite cluttered, he shrunk some of the more spacious content. Fortunately, he did not have to worry too much about the ban of underage magic. No Ministry official would dare to bother the Black family with such nonsense. In general, it was much harder to detect underage magic in an all magic family, so the ministry mostly ignored the issue. Finally, everything he wanted to take with him was safely stored in his trunk. Sirius sat down on his bed and took in his room for the last time. It was spacious and relatively bright room with a large wardrobe, a four poster bed and a sturdy writing desk. Both the desk and the wardrobe were made from ebony, one of the favourite materials of the Black family. The dark wood contrasted starkly with the red and gold Gryffindor banner Sirius had hung over the desk. He had toyed with the thought of taking it with him, but he had decided that it should remain here as a reminder for this parents how different he was. He had never particularly liked this room, but he had a feeling that he was going to miss it soon nevertheless. He took a deep breath, grabbed his trunk and walked to the door. Sirius gently opened the door a crack and listened for any sounds. The house was quiet. Regulus was staying with the Malfoys for a week and his parents seem to have gone to bed already. The coast was clear. The thought of Regulus saddened Sirius. They had gotten along very well in the past, but now they did not understand each other anymore at all. He should try to repair the relationship, but he had no idea how to do it. Maybe he would be able to talk with his brother at Hogwarts and explain the reasons behind his abandoning of the family. It was unlikely that Regulus would listen, but he should try nevertheless. Vowing to never set another foot in this house, Sirius snuck out of the front door and disappeared into the night.