Well, ah, I am sure the clarification would be welcome in some instances!

[In any case, he goes on to address her concerns.]

Of course not. I never thought you were malevolent! I was simply wondering if there was something of that nature at play within the school...

Furthermore, there's no secret to it! I simply worked diligently and put my all into helping to clean the classrooms while there were still others in the school! It is a simple matter of diligence. That's all there is to it!