The sorting hat never considered him for Hufflepuff. That might sound like an odd thing to mention, but people should realize that sorting is a very complicated business. There are infinite variations in the personalities of the children that may sit on that stool, but there are only four houses. Not everyone's sorting is instant, but there is an unspoken sort of a rule at Hogwarts that no one really volunteers any information about the houses where they did not go. There was never any danger of him being made a badger. He isn't loyal. He never has been. Peter has always been most concerned with Peter. He has had to be. It was not as though he was the sort that other people would be stepping up to look out for out of the goodness of their hearts. He was not a cute child or a charming one or one that was so sweet that little old ladies went out of their way to offer him candy the way that always happened to particularly winning children in stories. He was always average, regular, everyday sort of Peter.
He was not overly cunning or particularly ambitious (unless a dedication to one's personal well-being could be construed as particularly ambitious). That left out Slytherin. He was competent enough to get by, but he had no inclination toward working at making himself either studious or clever. That took Ravenclaw off of the list. There remained only Gryffindor in the running (and as he was willing to do whatever it took to make certain that Peter was well looked after, there was enough of what could be called daring involved to make it an acceptable fit). So, he had been sorted at Hogwarts and placed in a dorm with the boys who would become his friends. They were better friends, in fact, than he had ever given thought to having.
He liked being friends with them. It was nice to have people who were on his side when it came to dealings with the other students in the school. Even when he was with them, however, Peter still had to look after Peter. They liked their pranking. They had no ethical concerns with pranking each other. Sirius and James thought it quite funny to try to get one over on each other, and Peter and Remus were not exempt from their efforts. He might have minded that, but it had somehow never occurred to him to do so. Peter looked after Peter's best interest, and he was not averse to paying for the things that he had decided that he needed. The pranks and the laughs at his expense were a form of payment that left him with the protection from any outsiders that the Marauders gave each other. They closed ranks much like he thought siblings would if there were any outside threats. He liked that. It was worth it.
Besides, the others never grudged it when they would end up as a target in turn. They weren't hypocritical about it. They did not create their elaborate set ups and traps without expecting to be trapped and set up in turn. They had a good run of school years. He could not say that he had never had a moment's pause when it came to Remus's condition, but Remus had been so firmly established in his head as Remus by the time that he had learned about it that the new information could not completely overthrow that. He did worry about his safety for a moment, but Remus was always carefully out of the way when the moon was full. Besides, looking after himself meant making sure that his grades were good enough to get him somewhere after his school years were left behind, and Remus was always helpful.
It turned out that he did not get a regular job after school was over. He found himself in the middle of a war instead. They had never asked him if that was what he wanted to be doing. It was sort of taken for granted. The rest of them were so caught up in it all. James had his ideals. Sirius had his family that he was trying to prove something against. Remus would never have dreamed of leaving his friends to fight without him. It was not, he thought, that they had really meant to overlook him. It was just that they were each so devoted in their own ways that the fact that he was not was not something that they could readily see. James was loyal to a fault, and that fault was being a bit blinded about the people around him. Peter was his friend. He had no concept that Peter would not then be on his side.
It was ironic really - if you stopped to think about it. He, Peter Pettigrew, would have lived a quiet, normal little life that never would have attracted the attention of the Dark Lord if it had not been for the fact that he had friends who were a lot more attention grabbing. He would never have been approached were it not for his connection with the others. There would have been no interest in him, no reason for him to have to weigh his options and make choices, and no years of worry to his credit. They had made him their friend, and that had made him a target. He wasn't even sure that any of them realized that. He didn't think any of them were haunted by the dreams of the nondescript life that could have been his if only the sorting hat had made a different choice.
He was not loyal. You would have thought that they had known him long enough and well enough to know that about him, but they were always so sure about where they stood that they could not fathom that he was not right there with them. He was not loyal, and the Dark Lord knew it. He rather thought that the Dark Lord appreciated that about him. He was there through fear, and the man (or what had once been a man) knew that he would do exactly what was wanted from him due to that fear. Everyone knew exactly where they stood. There were no higher expectations. There were no disappointed glances that told you you had let someone down who saw you as better or different than what you were.
He hated being afraid. He hated worrying, but that was all that was left to him now. He still looked after Peter, and keeping Peter alive meant being afraid and worrying all the time and staying awake at night wondering which of them was the likeliest to kill him first.
This was not what he had wanted, but he had never been very good at getting what he had wanted. He had not wanted to be responsible for anything - let alone the kind of burden that came from knowing that you were the cause of deaths. It was not pleasant to know that. It was not pleasant to live like he was living, but the alternative was not living at all. That was what he wanted least. It always had been. He might not be comfortable. He might not even be safe, but he was alive. He still had a chance to get up and go on every morning. That had to be worth enough. He had traded everything else for it.