After traversing to the apocalypse, I am extremely delighted as a Demon Cultivator - Chapter 44

I, the protagonist, was just an ordinary NEET, but suddenly I was reincarnated as a tiny white snake in a fantasy world where legendary creatures and gods exist. Not only that, but I awakened in a cave as the offspring of a terrifying Medusa Serpent.Armed with only my human knowledge and my indomitable mental strength, I'm forced to use cunning tactics and rapidly evolving skills to survive against far stronger monsters and humans... So begins the survival story of a former shut-in with incredible willpower, living as one of the lowest-ranked beasts in a world of magic!ᆖMusic suddenly started playing in my head.I'd been waiting for this moment for so long.'Snakes! Assemble'....

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

David thought he would live a normal life when he awakened the banking system at the age of 18.However, fate seemed to have something else in store for him as his life turned upside down when following the death of one of his loyal client, a shiny window popped up in front of him.[Regretfully! You lost one of your clients today. However, the Bank of Eternal Origin can never suffer a loss.Even if he died, the client will have to pay back somehow, therefore his soul was captured. You now have the following options, keep in mind that you can only choose one.1 - Extract Client's Crystallion of Life (Money Talks, Grade - Uncommon)2 - Extract Bryan's memories from his birth till his death.3 - Any item that client owned in his lifetime.4- Do Nothing, let the compound interest do its thing and decide again when the Client dies in his next life.Please note as capturing the soul and imprisoning it requires a large amount of mana because of which you only have two hours left to make a choice.]

Kang Min-hyuk, the loser of the checkpoint, gained a high-level magical civilization and everything changed.