I have been reincarnated as a mob. Isn't that usually how it starts, right? But this development feels a little strange, doesn't it? Most people would be sad to be a mob, but then they end up having a significant role and overshadowing the protagonist. Well, that's only natural. After all, I know the story and work hard from the beginning, so it's only natural that I excel.... more>>

So, the correct way to express it would be like this:
"I've been reincarnated as a mob protagonist."
"I've been reincarnated as a mob."

To put it accurately, "I've been reincarnated as a mob in a popular novel. I'm a character who doesn't appear in the story at all."

Well, some people might say, "Hey, if that's the case, you're not even a mob!" But the thing is, that novel is popular, you know? It's been adapted into a game.

And I... <<less