Urethra Boner
When the piss you've stored in your urinary bladder starts going sicko mode and it gets harder and harder to move due to the pain, just like your dick when you get a boner.
Chad: The liquids in my body are moving everywhere! It hurts so much agh lemme sit down fam.
Derek: Ya homie lie down, that's a serious Urethra Boner.
Derek: Ya homie lie down, that's a serious Urethra Boner.