What is the best prank あなた can think of?

Just can't beat ghost pranks

Put clear ceramic ラップ around the toilet シート, 座席 and when someone goes to the bathroom (especially boys/men) their urine will spray everywhere. XD

nothings funnier than putting a piece of lint on your フレンズ head and yelling "spider!" XD it's so easy to do and almost everybody falls for it.