Strange is too busy focusing on his magic, trying to mull over which aspect of the wind to change next, maybe if the metal manipulation magic could make the thing move easier, that he doesn't realize Billie grabbing the bottom of his shirt until it's too late.

Needless to say, he wipes the hell out. As her foot connects with his knee, Strange falls to the ground with a thud. "Hell!" he swears, looking up at Billie with an incredulous look. "What was that for?!"