A cunt's picnic

A gathering of cunts.

Q: "You fancy going to that wellness festival on Walthamstow Marshes?

A: "No, looks like a cunt's picnic."

Can be abbreviated to "picnic".

Q: "Idles are playing at that wellness festival on Walthamstow Marshes, you fancy it?"
A: "No, looks like an absolute picnic."