Squeak.
I was going to say more here but then realized I have the things I need to work on the actual page now. But basically, there are seven known low poly rats in the game and it's been plaguing my mind ever since: The possibility of there being one more, so there's Eight of them in total? Like, the idea is there but I don't have any proof for it at all.
The known rats are the five ones present during the Elevator Ending, four in the room behind the boss's fireplace and the one in the corridor leading towards the press conference of the same ending, the one behind the van when approaching the Achievement Machine, and the one in the pink room of the Figurines Ending.