Angeliisms
Operating as the Death of Discworld had likely primed him for his summoning to Nautilus. By the time that he was Called, it was safe to say that he had a millenia worth of experience under his belt, and for all those years that included the observation of the development of the human race, well, it was very hard for anyone to not glean something from them.
As with most beings come into personified form by the ranged but solid belief of so many living things, Death had become what he was expected to become, to do what he was expected to do. He was the one in black that bore the scythe whom no one wanted to see, and who everyone dreaded seeing once they realized their time had come. There was always acceptance, but it was always a solemn motion, for what more could be expected when facing the End of mortality? And as those many mortals had done so, Death had dutifully accepted the reactions, the disappointment, and fear.
He tired of it. He hated it. He was sorry for it. Such were emotions not befitting of an embodiment of Death, and for the longest time he had successfully kept apart from such feelings. Death should be aloof, apart and perhaps even a little cynical. There were no bonds to be made, none to hold. He was the Last. While many could go before him, none could go beyond.
And yet slowly these qualities had changed in him. Humans had infected him, had intrigued and inspired him. He began to mimic their lifestyles, experiment and take up hobbies, pick up habits. And then he gained relations, some semblance of a family, and although the living knew better than to remain associated with the Dead, such ties lept across the chasm of possibility and reason, and the occult slipped into reality. But this isn't about his granddaughter.
Awakening in Nautilus, Death had slipped into the workings of things without too much trouble. It had been easy to find a familiar niche, and he was accepting of the situation. He considered it duty. The city had become his new area of jurisdiction, its inhabitants, his responsibility. Once he was able to, he transferred his cottage over, and with it, its shelves of Lifetimers and its library of autobiographies, all of which changed to reflect the denizens of the city and those linked to it in some way or another. After all, even on the Disc did Death have shelves of Lifetimers for the gods.
But these beings weren't just names on shelves or lines of text being constantly scrawled, nor grains of sand ever trickling in a ceaseless flow of time. They had come here, been brought to this city just as he. They had purpose. They had personality. And most importantly perhaps, they seemed quite open to conversing with a 7-foot skeleton in robes of absolute darkness. While of course there are still times that people are apprehensive about whether they should acknowledge, much less speak to a giant skeleton, for the most part they have been rather agreeable about the whole thing. They even like him, and Death would honestly be able to say that he liked them as well. He has come to consider many of Nautilus' residents as his friends, although it is only recently that he has really come to terms with the fact that he is his own being here, and that the rules he has often bent, back on the Disc, he is quite capable of working around, here. To be Death is to be Neutral, but when one befriends mortals, one begins to choose sides.
It has been a conflict he has wrestled with even before his time in Nautilus. He wasn't supposed to show partiality to anyone, and yet he had started to do so, so much that the Auditors had sought to have him replaced. But shouldn't he, as having become his own brand of Death, be able to make his own decisions? Hadn't he the right to forge companionships? With death not being a thing of permanence in the City of Change, surely he had to have more purpose than that which he had been named for. The matter had been spoken of between those he had come closer to in his time within the city.
They were just words to confirm the things that he knew but was afraid to let himself acknowledge. City of change, city of chance. Children liked him, and it upset him deeply when he could do nothing but watch as they expired. He had crossed the boundaries of his usual Duty when Sari had made such a simple but earnest request in asking that he pass on words to her "family," when he kept the restless soul of Zack company, when he made reassurances with Wheeljack upon Jazz's parting. He made friends, actual friends that actually cared and treated him like they would anyone else. It was a refreshing change. It was one he warned himself he should not get too used to, but one he so welcomed. And when the extensive and repeated deaths began to occur in the city, he became upset. Even before the frequent murders caused by Balthazar and Legato's collective efforts, Death found himself wanting to bring cheer to the city. He had hosted an Unbirthday party, which for the most part, was successful. And then the first winter holiday season he would be spending in Nautilus rolled around...
There was nothing to stop him from reliving (so to speak) that wonderful night in which he had taken up the role as the Hogfather and brought joy to people on Hogswatch Eve, and after careful research and conscripting a knowledgeable "pixie" helper for the night, Death eagerly set out to bring cheer to Nautilus' Wakened. It was the beginning of a deeper bond of friendship between him and the boy, Rex Salazar, which have since led to many a conversation and chances now and again to simply "hang out." The teenager had helped him to view his situation in a new angle, and Death came to rather like the concept of him being considered a "rebel."
Ultimately the decisions would always be his to make when it came to intervening. Thus far he has not forsaken duty for personal affairs, but he has allowed himself to be more directly involved with those he has come to care about. He has found himself capable of providing comfort and solace. He can show compassion and concern. Perhaps he will eventually even go so far as to prevent a death rather than stand by in wait. Freedom. Choices. Consequences. He needn't be given time nor breath to experience Life.