Definitions by ButlerX

resonant frequency 

When a guy fucks a girl at just the right speed to make her tits swing perfectly

She looks so ridiculously hot when I do her at her resonant frequency!

resonant frequency by ButlerX December 7, 2018

Lipstick skidmarks 

When lipstick gets smudged on a cock while giving a blowjob

She left several lipstick skidmarks on my cock last night. I loved it!

Lipstick skidmarks by ButlerX July 14, 2017