Shag time 

An arbitrary time at which it is the best time to meet or perform a particular activity

Nick: When are we meeting?
Laurie: Shag time

Shag time by chrisbox December 26, 2019

Shag Time 

When Scooby, Shaggy & the gang on the Scooby Doobie Do cartoon bring the bad guys to justice, and the meddling kids can finally relax and enjoy the victory - it's shag time...

When the Devil is on his knees begging Jesus to be his Lord & Savior, indeed we will know it's shag time...

Shag Time by Daughter of Diablo February 16, 2019

Part Time Shag 

A bloke or lass that you have no emotional connection to who you shag... a lot.

I don't need a relationship I've got a part time shag.

Dude I think my part time shag is developing feelings for me.

You're now in a relationship with your part time shag, you're a faggot.

Part Time Shag by Princess Twilight Sparkle May 28, 2011

Long time no shag 

What you say to someone with whom you have had one or more previous sexual encounters. Primarily used to

1. Announce sexual prowess and coolness to the general public.
2. Display lack of shame.
3. Humiliate the person to whom the comment is directed, automatically making you the winner and czar of all things excellent.

Ethan: Yo Melissa! Long time no shag, eh?
Melissa: Go fuck yourself Ethan.

Long time no shag by puertorican120 June 30, 2011