Global Reincarnation: Only I Know the Plot - Chapter 875:

Shion, the ‘Hero of Darkness’. He was said to be the strongest hero ever. He believed one thing, and that was his current party members.

“I’ll defeat the Demon Lord with this party!”

That is what he swore to do, but a tragedy occurs. He was painfully betrayed by the girls that he trusted.

He barely held onto his life, but the incident left a deep scar in his heart.

He gave up on living, and while he was wandering around in a forest, looking for a way to die, a single monster appeared in front of him.

“Will you kill me, please?”

The monster asked Shion, who was still strong, despite losing his powers.

What Shion, who wanted to die as well, did was―

I originally thought this was a world like an ordinary urban novel…Drawing comics by myself, traveling is pretty good.
But tell me, what happened to this magician called “Emiya Kiritsugu” who jumped on my face?
Who changed the settings?
Currently involved in the content of “F/Z”, “F/SN”, “Fantasy Carnival”, “The Emiya’s Meal”, “The Holy Grail of the Imperial Capital”, “FLA”, “Elmello II Event Book”, “FGO”, “FE”, etc.
Others related to “JOJO’s Bizarre Adventure”, “Rebellious Lelouch”, “Persona 5”, “Attack on Giant”, “Death”
“FGO”, “FE Series”, “FA”, “FSF”, “Cangyin”, “Magical Girl Illya” will be involved next…

- Description from novelbuddy

In the year 3000, humanity was forced to leave the earth when a sudden mutation caused more than 70% of the planet's population to mutate either into zombies, werewolves or vampires. The humans put up a fight but didn't have a chance against the united front of the monsters and they were forced to leave. At least those who were rich and lucky enough to leave.

A century later, the chaos on earth had calmed down but the humans who were left behind were treated like slaves and were forced to join one of the three factions: The Undead, The Cold Ones or The Lycans when they turned 16.

It was a similar story for Ashton, who was one week away from being turned into one of the monsters as it was his 16th birthday. He decided to run away from his fate and join the secret resistance to battle against the monsters.

However, his plans came to a standstill, when a series of misfortunes leads him to be bitten by a Zombie, a Vampire and a werewolf before either of his powers could manifest.

He ended up receiving all of their powers, but at the cost of his humanity. Yet, he wasn't willing to let his humanity die. No matter the cost.

Will he be able to live his life, or was it already too late? Which faction will he join? Will he be able to find the secret behind the mutation?

There were too many questions, and only one way to find the answers: follow Ashton's journey as he fights back to retain his humanity.

A surgeon accidentally got the blessings of a system, shocked the medical industry, and rejuvenated countless people.

- Description from Novelupdates