A sex act. The Fatmans Hammer is a follow on from a regular Blowjob. Whilst being Fellated you slowly lift your arms and your legs until your whole bodyweight is being held purely by the Fellators mouth. To finish the sex act flawlessly, you must start to spin, clockwise or anti-clockwise, until you make a full rotation.
Awesome Dude: I was getting a blowjob last night

Other Dude: mmm-hmm

Awesome Dude: And I started lifting my arms and legs until I was suspended purely by her mouth.

Other Dude: mmm-hmm

Awesome Dude: I then did a FULL rotation, clockwise.

Other dude drops his monocle into his fresh cup of Darjeeling tea

Other Dude: Dear god. The Fatmans Hammer. I thought it was a myth!

*Awesome air guitar for 35 minutes, the loch-ness monster and Bigfoot start making out, fireworks and fucking awesome laser light-shows ensue. The amount of high-fives worldwide increase by 480%*
by TheLegendaryFatmanHammer March 11, 2014
Get the Fatmans Hammer mug.