The Author is an Extra, The MC is a Reincarnator

Summary:

Zaiden Archman. He’s the main character in my novel called ‘Awakener’s Dead Harem’.
As an author, I love it when my main character suffers and is depressed.
He’s the main character that I took pride in. With my novel about to end, I pushed myself to write the last volume.
However, what I never expected was that it would be the end of me too. When I opened my eyes again, I had become Vincent Dihart, an Extra in my novel, who is only mentioned a few times in the novel.
I then found out a sad truth about my Main Character that I took pride in. He has changed.
He’s not the Main Character that I made. He’s a Reincarnator. Someone has replaced my Main Character. And that someone has read my novel.
I feel empty and betrayed.
As an Extra, I will not be able to save this world from danger.
Only the Main Character is the one who can save this world. But, he will also not be able to do it without being depressed.
So the answer is clear.
“I will make him suffer.”
This is my story about living as an Extra. And once in a while, messing with the Reincarnator to make him suffer.