So...

My housemate has asked me - post factum - if it is alright that she borrowed one of my books to level her projector.

The book is not a first edition, or anything (and yes, I did notice the gap on the bookshelf; and yes, I do know precisely which book it is), so I said it was fine, and it was. Kind of.

Let's say this housemate is a chef. It occurs to me now to wonder how she'll react when I borrow her food mixer, dehydrating rack, or imported Japanese knife-whetting stones to prop up my 'overflow' bookstacks...