Term used to describe a person who always has his/her fingers in the anus. The person may do it for the simple pleasure of 'getting' that itch or because they are exactly just that - fiddle bums. Some also like to sniff their fingers after getting in *deep*
Can also be used as fiddle butt to describe somebody who does that in public. Fiddle fingersnail- nail or finger that has traces of being in the ass
Jammie: Hey Jack, what the hell do you think your doing?
Jack: Nothing man. Just scratching. Nothing wrong with that *shrugs*
John: walks by and says fiddle bum and walks of laughing!
Jammie to Jack: You always were a fiddle bum/ass/fingers/nail