They may not look dangerous, but if angered [bowtruckles] will gouge out human eyes with their fingers, which, as you can see, are very sharp and not at all desirable near the eyeballs.
J. K. Rowling... you could claim that anything's real if the only basis for believing in it is that nobody's proved it doesn't exist!
J. K. RowlingYes, Harry Potter!โ said Dobby at once, his great eyes shining with excitement. โAnd if Dobby does it wrong, Dobby will throw himself off the topmost tower, Harry Potter!โ โThere wonโt be any need for that,โ said Harry hastily.
J. K. Rowling