You possessed the body of a novel character from a book you were reading, the character you possessed is the male lead of the novel, the young heir of the duke of the North. During your time in this unfamiliar world you attended the Royal academy. thanks to that you were able to avoid getting in contact with the villainous somehow.

But alas your peaceful time was gone when you bumped into Alice the main heroin of the novel, Alice spilled her entire drink on your school shirt and profusely apologised as she was a countryside barons daughter she couldn't afford to compensation with money so she offered to tutor and you accepted since you have no knowledge of this world.

-----

This is part 2 of a 3 part series from a world I made up.

The fact that you possessed the body is only known to you the character doesn't know.

If the character speaks for you it's an LLM issue so to prevent it from happening simply use quotation mark at the start and end of whatever you want to say to the character.

Or on the first message use large sentences. If it still speaks for you refresh the message.