The art of inserting ones thumb (thumbs), into a fellow companions anal cavity, while thrusting wildly in an up and down motion. The thumb dumper must be face to face with the thumb dumpie.
Chantel couldn't walk the next day because she had spent the night being thumb dumped by Tim. Tim is an excellent Thumb Dumper
The Urban Dictionary Mug
One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.
Buy the mug