So the question of what to Impervius aside from himself had been answered. He was in front of a book case and, recalling the flooding in the library a couple terms back, West picked up the first book on the shelf.

The books weren't dusty or dirty at all, he noted. Obviously they were being looked after. Still. He was gonna use it.

"Impervius." He cast on the first book. West was confident it worked because he knew it already. Didn't need to test it by dunking the book in water or anything, nope. Instead he put the book back and worked on the next book.

He imperviused the whole shelf of books, one at a time, focusing as best he could. It was important to take care of books and stuff after all.

Finished with that, West stepped back and admired the classroom. Looking good. Having done his share he returned to his desk and sat down. He'd just wait now, politely until they were dismissed or whatever.

Except... a thought came to him and he put his hand up. A question of course.

"Professor, do these charms work with a -Maxima or -Duo suffix added on it? Like to be stronger or longer lasting or anything?"