eiffel towel
A variation of the prison fifi (where a prison inmate rolls a towel very tight, inserts a rubber glove into the towel, lubes it, and then proceeds to have sex with the towel). This variation consists of two men "hitting" both ends of the towel (requiring two gloves) and high-fiving each other in the process, hence the eiffel towel.
Wow, I'm really lonely brosef, we should do something constructive and get our eiffel towel on...