A phenomenon affecting the gentleman when on long car journeys. When the natural harmonics of the road vibrations through the car at cruising speed, cause a usually unwelcomed lob on (aka semi, chub on, semi erect penis) for no apparent reason. Indeed you could be thinking of things entirely un-erotic.

Usually affecting the gentlemen passenger, but will hit a driver after a while. There is speculation of 'Journey Juice' affecting women, but this is unconfirmed.

the thing that you don’t have when you’re phones percentage is over 20