to masturbate while watching an unknowing friend sleep on the couch.
I don't care how drunk he is, you better give that mother fucker his keys before he frienderbates all up on your living room floor.
When you masturbate with or with your friends while talking about sexual scenes. When a guy frienderbates he masturbates with his friends while talking about girls he had sex with or girls he wants to have sex with. When a person calls a guy a "Frienderbater" the guy will find it offensive and kick you in the penis. If you tell that to a girl a girl will kick you in the vagina.
Tim: Hey Lucia what did you do yesterday? You didnt respond my text until 26 minutes. Lucia: oh. I was frienderbating with Ann and Nikki Tim: oh. o.o .. well i frienderbate too *lies*