Mc is lowkey kinda dumb here. Like I get hes angry and all that, but why are you trying to fight a guy that's clearly much stronger than you? And why are you arguing over that job? If they've decided to fire you it's clearly not in your best interest to be working there anymore. Even if you do somehow convince them to let you stay (which is very unlikely) they're clearly going to keep treating you like cr**. Just take your severance pay, leave with your dignity intact, and go find another job somewhere else where they'll treat you right. Getting emotional like he did never ends well.
I feel so lonely i want to die. I have no hope in this life.
Spoiler!
Oh, I can't change what I am right now, but I'll be fine in the next life! Going all in on that isekai/transmigration baby!