Unsolved Mystery

Mystery?? Sounds exciting eh?

Furriends, have you spotted anything unusual from the above photo? ... erm... besides me not looking at the camera...

 If you'd not, here's a clearer pic:

Here's the answer:

It still baffles Mom till now, that my arm (yes, always just ONE arm) can always slip out of the armhole. It happens with other clothes too and they are not over-sized!

Clue: it happens only after I've rubbed and rolled myself silly on the bed ^_^.