Even the best people can improve. When it comes to missionary boys, something as simple as not knowing how to follow the rules or having doubts about their faith is enough to get them kicked out of The Order. If they want to be worthy or get a clean slate, they'll have to be taught a lesson by their superior. The missionary boy will be blindfolded as they get spanked, fucked, and used in any way their superior sees fit. This sounds like a drastic measure, but offering their ass, mouth, and dick to The Order is the best way to show their commitment.