🎨 Black Spotted Tortoiseshell Tabby

Huh, you're right, that's very peculiar. Theoretically it's possible she's just a tortie with an unusual pattern, but in this specific case i think it's more like to be some kind of mosaicism. Chimera is not the only option (there are somatic cell line mutations, for example), but it's certainly possible (if the parents' colors allow both red and tortie daughters; so if her father is red and her mother is tortoiseshell).

black tortoiseshell with low white spotting (calico) !

Black blotched tortoiseshell tabby with white

That is a very serious face for her to make when I know just yesterday she was playing fetch

Perhaps you did not yet know that Nym is perfect but now you do.