Soooooo old Johnson was a POP... what's a POP you may ask?
A 16 year old Etonian blogs from inside the bubble
theetonboy.blogspot.com
I just want to extract one paragraph from the above article...
As with anything that’s highly sought after though, becoming a popper is not easy. There’s no application process as such, but you have to stand out in such a way as to be eligible for a leadership role. In most cases this is by being GOOD AT SPORT but in can be in other areas too, music and drama for instance.
....so I'm guessing he specializes in drama then!