Thor does one thing consistently: he comes a running when I ask him if he wants to "toothbrushie".
1. That is his personal toothbrush. I'm crazy, not insane.
2. Towards the end, that is Thor slamming his face against the toothbrush, not me smacking him.
Thor has been doing this since he was a kitten. Loki started joining the party about six months ago just to do his weird mouth smacking thing.