Matron said that she caught you wanking last night in the dormitory. I'm sure you know that we cannot allow that sort of behaviour at school. It simply will not be tolerated. You know you're going to be punished. You haven't been sent to my office before so I'm going to explain exactly what's going to happen to you in detail. You are going to be spanked with my hand, the plimsoll and then caned. You will also show me exactly what you were doing in the dormitory last night! Needless to say, you will be leaving my office with a very sore bottom.