Definitions by Dr. Brown finger

Thumb Club 

The club one joins after having inserted his thumb into his wife or girlfriend's anus while have doggy style intercourse.

Dude, I joined the thumb club with this chick last night when I was pounding her doggy style.

I joined the thumb club with this girls last night. Check out my chocolate wedding ring. lt came with a corn kernel diamond.

Thumb Club by Dr. Brown finger November 9, 2013