She'd drain a bag

It's what you say when you see a hot sheila, and is also another way of saying, "I'd fuck her".

Drain a bag = drain ya balls

Two dickheads takin a stroll at the shops and one of em spots a hot sheila.

Dickhead #1: "oi! Shes fuckin hot ay!"

Dickhead#2: "awwwh fuck yeah cunt, she'd drain a bag!"