The time stopped for us.

'The time' is used for talking about a specific event. For example: 'The time when we went to the shops'.

I was going backhome from a tiring day of school where nothing seemed to go my way.

TAs the sun was setting, I looked up at the bloody red sky, and wondered: when are things going to get better for me?

I stopped and watched the sunset, breathing quietly, numbing my feelings,. I had kind of gotten used to shutting down my voices and just letting time slip through my fingers without me realizing.

I decided to continue on my way to the library I always go to.

Reading makes time flow for me, - it makes me live new lives and forget about my own.

I pushed open the door and expected the librarian to come and recommend me the latest work of my favorite writers, as he always does.

But he didn't, i. It seemed strange to me, and as I was looking for him between the gigantic library book cases, my eyes meetedt the clock hung on the wall... it wasn't moving at all.

I took a look at my phone and it was indicating the same time as the clock: 6:52pm.

This is fine grammatically, but it would sound better to just say:
'I took a look at my phone and saw it was 6.52pm, the same time on the clock.'

I tried to turn a blind eye to all of this,. "tThe clock is probably broken, your phone is just not functionning correctly, it's all a coincidence".

TSuddenly, the librarian suddenly showed up and took back the book aggressively.

He held my hand and said in the sweetest voice that i could hear worriness throughout "you have to come with me", "You have to come with me". I could hear the worry in his voice.

I think splitting it into two sentences sounds more natural to me.

I trusted and followed him without saying a word,. I didn't know where we' were going andor why, but I trusted him.

As we were running, iI noticed thatere was no trace of any living person was to be found, i. Was there just him and me left?

I didn't realize when and how but we arrived ato the top of a mountain, and I saw a big rock in front of us.

'Mount' is usually only used for the name of a mountain (for example, Mount Everest). It sounds odd to just talk about 'a mount'.

I tried to ask Arthur (the librarian) about it but he spoke first.

"Do you remember the book I took back from you earlier ?

That's the book of the five masters of time, y. You are one of them, but you're a little different: you were born to be thea master of time andbut you wasted it emotion-lessly,. I watched you every day being depressed and wasting time, being completly neutral but iut I couldn't tell you anything because it was supposed to be anthe ultimate secret.

'being completely neutral' is a bit unnatural. I think it's fine to leave it out. Or replace it with 'never doing anything'.

I, master of trust, should now get punished withime, will now lose my life for telling you, but before that happens, I need to ask you: do you wannat to sacrifice yourself for the sake of humansity and time... or do you wannat to live your life as you used to, and live asbecome the master of the Earth dimension?

'Punished with my life' is an odd expression.
'Wanna' is fine but it sounds surprisingly casual here. It's an odd tone shift.
'live as the master of the Earth dimension' - 'live' is repetitive since you used it just before.

He seemed so worried and sad as he was talking, and hearing him say that he willould die was the most heart-breaking thing i'veI had ever experienced: I loved him!

But now, what was more important is whatwas the question he asked me.

I think 'the question' sounds more natural than 'what'

I thinkedought about it and even though the second option would have been so tempting, iI realized that those humans didn't do anything to deserve just disappearing like this, tat. They haved the right to live.

He looked at me and said "I knew you wouldn't be selfish, n. Now we are both bound to die, but iI want to confess to you first what iI couldn't tell you for years." He wiped my tears and said "I love you!"

All my worries disappeared, only. Only the two of us mattered.

On Earth, everything got backreturned to normal, p. People and time got back to their usual race.

'their usual race' sounds strange here and I'm not sure what it means.

And my soul, along with Arthur's, waited for billions of years... until we gotwere reincarnated again, as our 'sins' gotwere forgiven and our love gotbecame stronger.

Now, we gothave each other, forever.

'Got' sounds very casual here and a bit weak. 'Have' sounds more romantic.