I'm no detective, but...

The following evidence has presented in the case of the Icky Disgustingly Dirty Never-to-be-used-again Toothbrush.

Exhibit A:

Exhibit B (basically just a close-up of Exhibit A):

Exhibit C:

Exhibit D:

Exhibit E (Just couldn't leave this one out... it doesn't actually add much to the case):

I think Miles might have been the one who ruined my toothbrush. The punishment for his crime: Lots of hugs and kisses and a big cup of milk. The judge was lenient since he's a first time offender.