Why? WHY?

Dear (I cannot think of a suitable appellation - help?),

I don't care if the bookshelf IS right next to the pencil sharpener. You must - MUST - restrain the urge to scrawl the F-bomb on MY BOOKS. First of all, it is not appropriate language for school. Second, the book is not yours to decorate. Third, I should NOT HAVE TO TELL YOU THIS!

Double-ewe. Tee. Eff.

*glower* Grrrrrrrrrrr.