Death harvests the souls of the departed, and will pursuit rebellious souls who refuse to accept their fate and try to escape. He would also approach soul-dealers for souls they've kept from him, and would fight them if he had to.
He has a powerful aura that is repulsive to people and animals and stirs up feelings of fear/anger in them, and - there is no better way to say it - it stinks of death and rotting flesh that not even flies would approach.
At times, he would assist protagonists in plights and protect people who are destined to die, but most of the time he stays on the neutral side. After all, in the end, there is no justice. There is just him.
But it would not stop him from caring or helping those who truly need him when there is no one else to go to.
Death had existed since the end of the first life, and has been around ever since, reaping souls of people who've died and chasing after those who try to escape him. It is worth noting he has never killed anyone, and is simply the guide, taking the souls over to the other side. He gets upset when accused of killing, and when people fear him, just because he is just doing his job.
While Death never truly has enemies -or, more specifically, formidable foes who posed a danger to him - he has to deal with monsters. Corrupted souls, to be specific. They are originally normal souls who escaped him for too long, usually killed from a massive trauma or in horrible pain, and over time, they would become insane as their souls corrupted with an immense hatred for him. They would eventually adapt physical forms as they continue to refuse to leave the mortal plane, but they are deformed, corrupted shells, former shadows of their human bodies, and would attack anyone they sensed Death's aura on, as long as even a little bit of human weakness is shown. The purer the soul, the more dangerous and powerful the monster. They would continue to avoid Death, however, because they still fear him. They are invisible to the mortal eye, thankfully, and would leave them alone. They are constantly suffering, and the only way to help them is to put them out of their misery.
Death had never truly involved himself in the mortal world (aside from one occasion where he chased an obstinate young child soul for three months) up until when he fell in love with a woman, Selene Screech. He took the form of a human vulture named Damian Door when courting her to avoid public attention and for her sake, and she soon reciprocated his feelings as they got to know each other more.
However, she was constantly in danger, from being too near Death. His aura rubs off on people who gets close to him for too long, and it attracts the monsters. Despite the danger, Selene loved him and refused to stay away from him. She could easily run from one or two monsters, and a good shower removes the aura.
The real disaster struck when she got pregnant (which was a huge surprise, because Death thought he could only take life, not give life) and she was being hunted by monsters 24/7 from the aura radiating from the unborn child. He would try to convince her to get rid of the child, but she loved it too and wanted to give it a chance at life. Death never gave up, but he did his best to protect her even as she got more and more pregnant. Unfortunately, he accidentally let a few slip through just as she went into labour. She had to run right after laying, chased by the corrupted souls, and eventually found a safe place to hide her egg. She used the baby blanket to throw off their scent and tried to escape them, but, weakened from her labour, she was ultimately surrounded and ripped to shreds. Death caught up too late.
And just after the attack, Death still had to do his job, and was in a moment of weakness, grieving over Selene's passing. He was in the Negaverse for a mission and when he saw the Nega-version of his lost love, he was unable to resist. She had also been very flirty with him, seducing him, and they spent a night together, with him siring another child.
Since then, he'd distanced himself from mortals for good, but he would occasionally watch over the child who belonged to Selene. The egg was adopted by a gypsy family and named Victor when he hatched. He'd bounced around families as they found him repulsive. He inherited his father's aura. But eventually he was able to settle down with a family who loved him. He was very safe, as he was constantly around people and their mortality masked his aura, but he was still subjectible to monster attacks. In his mid-teens a monster cornered him and blinded him in his right eye, right before Death showed up to protect him, and then erase his memory of that event so he could still have a normal life.
Death would soon approach him again in his adult years and return his memory to him, asking if he wanted to join him and learn more about the other side of his origin. Victor turned him down because he wanted to be with his friends and family, and Death accepted it and left. He would still visit from time to time.
His other son, in the meantime, had been on the streets, fighting monsters and defending himself, and was taken in by Death, who took a while before he realised he should not impose his bitterness upon a blameless young child. He became Death's proxy and would frequently hunt down sadistic killers and corrupted souls.
Not many people are familiar with Death, but the people who do knows him as A MASSIVE DORK. He is very fascinated by mortal life, and would sometimes imitate them in what they do. Unfortunately, sometimes those involve pranks, jokes, and memes (especially the dead ones). He can be unnecessarily dramatic at times and gets very emotional when accused of being a monster and a murderer.
Existing for several millenniums, he has acquired a knowledge in many fields. He is still eager to learn, as there is always something new to study everyday.
He can be friendly and kind, and is very good with children. However, he does not care for deals and trickery, and would follow his duty to the end, which sometimes makes him come off as cold and uncaring. In rare moments, he would show a good amount of sympathy and find a loophole just to allow a mortal to continue existing, or to even escape him just for a little while.
He speaks in bold, and has a deep, echo-y voice like granite coffin lids scraping against each other. It can send chills up your spine, but it becomes hypnotising and pleasant to listen to after a while.
Death had appeared once in the Darkwing Duck series, when he came after Darkwing's soul in Dead Duck. It had been a few decades after Selene's death, and he was better at dealing with his grief.
He soon met Gladstone Gander, when the lucky goose was struck by a killing spell. As his luck did not allow him to die, Gladstone only encountered a series of deadly events with Death showing up each time he was supposed to die, only for his luck to prevent it. It caused him to tire of his job, and his curiosity towards mortals returned to him, making him realise he missed being around them.
From then on, while he continued to do his job, he would make appearances among the friends he'd made… even if he knows he would have to take them or their loved ones away one day.
In the early 147BC, while Death was solely focused on doing his duty, he encountered a very young child who had died from starvation. However, before he could harvest his soul, the boy evaded him and stole his scythe. Death chased him around the world for three months, where people continued to die but were unable to leave the mortal plane, and little by little, he learnt about the boy and his love for life and joy. He learnt to see the world through the eyes of an innocent child, and they started to form a bond. But, in the end, Death still had a duty to do, and he made the first deal he'd ever make with a soul. He would take the boy to visit the faire he had always longed to go to, and he would follow Death willingly. And so it was settled. Death made sure they both had fun, and when it was time to say goodbye, he returned to his job, a completely changed entity.
Selene was his one and only true love. She was born in a middle class family in the late 50's, and was a fearless, happy and optimistic girl who was close with her grandfather, until Death came to take him away when he died of a heart attack. Selene was gifted with a supernatural sight that allowed her to see the dead and even Death's true form, no matter what form he took or how much he did not want to be seen, and during their first encounter, she'd attacked him, suspecting him to be the cause of her grandfather's death.
Even after knowing who he was, she was not afraid of him, and soon fell for his charming and quirky ways when he started to court her. She did not mind his true form, and encouraged Death to love himself the way he looked. According to her, the time spent with him was one of the best times of her life. Even when she died, she had no regrets about meeting Death. Her last wish before he sent her away was to care for their child, and to continue to smile, promising him she'd see him again.
While he constantly watched over his son, he never approached or personally cared for him, not wanting him to meet the same demise his mother did, and wanting to give him the chance his mother had died to give him; a normal life. For a long time, Victor would describe a strange man watching him from afar, invisible to everyone else but him, and always felt comforted and safe with him around.
When Death finally revealed himself to him, he was not angry, instead thrilled that he could meet his father. However, he was content to live as he was currently living, not interested in learning more about himself. Death and his half brother were forever welcome to visit, however, and he would always be prepared with cookies and tea, and an eagerness to help whenever he was needed.
Darkwing Duck had been a difficult soul to deal with. He fled the cosmic plane and constantly evaded Death when he came for him. At one point, Death wanted to test the hero's nobility, as St Peter and Beezelbub continued to argue over his soul, and when the opportunity arose, took his neighbour's soul, Herb, instead, and was surprised at the results. He continued to remain stoic and serious, refusing to give in, but Darkwing was far more stubborn than he could ever be. After realising how much he was needed in the mortal realm, he let Darkwing continue on with his life after wiping everyone's memories of his death, save for Darkwing, but human minds always had a funny way of reasoning, and sure enough, the hero quickly wrote it off as a strange dream.
He still gets headaches thinking about Darkwing Duck, and hopes he would not be seeing him anytime soon.
Death was initially annoyed at Gladstone and his refusal to die, but as soon as he realised it was a curse and not a prank, he assisted Gladstone in removing the curse, and then leaving him high and dry on Mt. Vesuvius.
He eventually became his occasional roommate and friend.