The suction cup was not very strong, and it seemed liable to fall over on its own because it is so small and lightweight, so I glued it to a cool rock. Works like a charm.
It is cute and works as intended, I just didn't realize it only holds one toothbrush. I'll probably end up buying another one so both my kids have a toothbrush-cat... It's so cute that they are arguing over who gets to put their toothbrush in it, lol.