Reincarnated as a mob character. Doesn't reincarnation usually start this way? But isn't this development a little strange? Most people would be sad to be a mob character, but I'll surpass the protagonist with my actions. That's only natural. After all, I know the story and I'll work hard from the beginning.
Therefore, this is the correct way to express it:
I reincarnated as a mob main character.
I reincarnated as a mob character. To be precise, I reincarnated as a mob character in a popular novel. A character who doesn't appear in the story at all.
You might say, "Hey, that's not even a mob character!" But that novel is popular, and it was made into a game.
And I'm in the game...