four-balling 

Two men riding together on the same motorcycle or scooter.

Fred: Hey man, can I get a ride on your new Harley?

Tim: No way!

Fred: Why not?

Tim: Dude, that's four-balling - and not cool, especially on a Harley!

four-balling by Pastcha July 28, 2014

Furballing 

The act of giving a blowjob to the point of ejaculation, letting him cum in your mouth, and then spitting the cum out on the nearest cat.

"Did you just pet the cat? He's all sticky and matted."

"Oh damn, Amanda must have been furballing on him last night."

Furballing by A-Dazzle September 28, 2012