Sweet mother of Satan's left testicle 

When you see an absolute unit of a fucking spider on the ceiling but you have friends over so, being the comedic relief character in your own life, have to tell something funny in terror.

Sweet mother of Satan's left testicle get the fucking flamethrower, Jerry!

Sweet mother of Satan's left testicle by WreckWrack October 22, 2018

You gotta be fucking my left nut 

Usually said when something would make your life harder to live in, or would make your tasks harder to do

“Bro did you hear, Mr. Tomasulo input our math test grade” “You gotta be fucking my left nut”

You gotta be fucking my left nut by Real Ram October 9, 2019

I felt cold, so I left. 

A diplomatic way of saying "f*** you" when someone is ignoring you, being rude to you, giving you the cold shoulder, boring you with superficial talk, not showing they care, being cold and insensitive, etc.
The statement doesn't have anything to do with the weather but everything to do with how warm and caring someone is towards you, how interested is a person in your conversation.

He/She ignored me the whole time. I felt cold, so I left.

He/She doesn't care. I felt cold, so I left.
He/She gave me the cold shoulder. I felt cold, so I left.
He/She gave me a sly look. I felt cold, so I left.

I felt cold, so I left. by O'Hara Eyes October 25, 2018

back and to the left 

Used to describe someone who has been assassinated. Related to the JFK assassination, as quoted from the film JFK.

"Dude, did you see his head explode? It was all back and to the left and shit!"

back and to the left by Amy D. April 26, 2005

Facebook Left 

When you click on the first picture on someone's profile and hit the left arrow to see what the person looked like when they first got a Facebook profile

"Yo that chick is so hot! Take a Facebook Left to see what she looked like in high school!"

Facebook Left by Abdullah Fata'ai August 24, 2012

Who left

Your dad

‘Dad, who left to go to the shop for milk and never came back’

Who left by Factz119 August 3, 2019

There's No Blue Left In Your Eye 

It means that someone is lying.

John: "I wasn't with your girlfriend last night."

Mark: "You're lying! There's no blue left in your eye!"

There's No Blue Left In Your Eye by Infidel21 March 22, 2009