Natsuki Subaru, Sin Archbishop of Envy

Prologue

AN Starts during Ayamatsu (Pride If) when he is dying continuously trying to defeat Elsa without Reinhart's assistance. Another non canon aspect each time return by death is activated Satella gains a small amount of mana but the seal drains the mana overtime but since he keeps dying continuously in loops that last a few hours so the mana builds up enough for her to do something.

3rd POV
As the endless black void pans onward two figures can be seen in the distance. One with beautiful silver hair and shimmering amethyst eyes with a black dress holding a yellow flower. On the other side we see a being made of shadows, unmoving and quiet. If you listen closely you can hear the woman's pleas... 

"How long do you plan to let our beloved suffer? How long will you let him go through the tortuous path we set him upon." 

As she got no response from the shadowy figure she fell into meaningless silence for the last time in the four centuries she's been alone.

We now see a young man on the brink of insanity as his gruesome repeating adventure starts to truly take a hold of his mind. The man's dark black hair is disheveled and his once compassionate and confident eyes were now filled with insanity and hopelessness, as he slowly bleeds out he feels the pull of time again but he realizes something else is about to happen as a black void of shadows envelopes him.

(Technically) A Few Hours Ago
We see an 18 year old boy with black hair and what seemed to be a constant sneer on his face shopping. As he picked up different chip bags and compared them. After setting one bag down and grabbing his flaming hot Cheetos and a manga he went up to the cashier and paid for his items. Once he left the store his eyes started to hurt and this is where the fun really begins.

Natsuki Subaru POV
As I walked out of the store my eyes started hurting, it feel like they're on fire. I decided to rub my eyes to relieve the pain. When I opened my eyes again I was in a new area 

'What is going on? This isn't where I was, did I get summoned to another world? Oh hell yeah!' I thought my mind going a million miles an hour.  

3rd POV 
Once Subaru looked at his surrounding thoroughly he came to the conclusion that he was in a medieval era world with a fairytale setting with magic and monsters. Once he started exploring he learned the people speak the same language but have a different writing system than Japan.

After exploring the capital he walked into an alley and sat down to take everything in. But before he could do much three thugs approached him and started to try to mug him "Gives us everything you got, or else". Before things could get physical a small blonde girl came running into the alley from behind the thugs and jumped over the wall and kept running. Not much longer after the blonde girl a silver haired girl with amethyst eyes came running into the alley. 

"Give what you took from me back!" the silver haired girl demanded as everyone else looked confused.

Then a floating gray cat like spirit came from behind the girl and said "Are you sure Lia, these are all guys."

As all of this is happening Subaru Is becoming infatuated with the mysterious silver haired girl, little did he know soon this infatuation would turn into delusion as his sanity slowly broke.  

Time Skip 

Sometime later Subaru learned the name of his savior 'Satella' and he was on his way to help her find her insignia. After a few hours they stumbled upon a run-down area of the capital called 'the slums', they decide if the thief was in the capital she would be here. After walking though the slums for about 15 minutes the cat spirit named Puck had to leave to the mana strain of his appearance. Eventually they found what looked to be a run-down bar. After conversing they decided Subaru decided to go in first, which would prove to be a fatal mistake...

Natsuki Subaru POV
'I'll finally be able to impress Satella when I get her insignia back' 

As I opened the door and stepped in and started to feel like something was wrong. The further I walked in to investigate the worse the feeling got...  

'Why is the floor so sticky? Is that a person on the floor? Is that the thief girl?'

At this point the feeling the was unbearable, like I was walking the line of life and death... That's when it happened. I felt like I got paper cut on my abdomen. As I touched my stomach my hand got wet and started to feel weak. As I fell to the ground and my intestines fall out of my abdomen and I see a woman with dark hair and a slim fit outfit licking a liquid off a curved metal blade.

As I feel my conscience start to fade I remember Satella 

'Satella! I have to warn her so she doesn't get hurt!'

"Subaru, are you okay?" He hears Satella say from outside.

'No stay outside! Don't come inside! You'll die'

He hears the door open and Satella say "Subaru, where are you?"

'NO NO NO YOU NEED TO GO BACK OUTSI-' He stops thinking when he hears a thud and sees Satella body fall next to him. As he tries to reach her hand he swear to Satella "I will save you" he takes his last breath and dies.

This is first of the many deaths of Natsuki Subaru, The Sin Archbishop of Envy.