Droopy drawers informal noun
Used to refer pants that are sagging below the waistline. Sometimes, it is used to refer to someone whose pants are falling down.
I think schools should ban students from wearing droopy drawers.
Droopy drawers! Pull up your pants before the teacher comes!
To pull one's underwear or trousers down
If you fall for someone's trick the first time then they are at fault.
Are you going to mess with me again? Fool me once, shame on you; fool me twice, shame on me.