And pokes you in the butt?
Go for a walk. Keep your eyes open. See what you see, not what you're looking for.
What? What is it this time?
Look, there, on the window ledge. Spikes.
Spikes.
Long ones, preventing you, if you should want, and the ledge is the right height to be tempting, from parking your backside on that ledge for an hour, or a minute, or even a second.
Instead, you keep moving because you have to. Obviously, this is not your place to perch, nor is it anyone's.
The spikes can be — what? What can they be?
Well, wrought, for example. Like some I saw just a day ago. Wrought, or worked by hand, of iron. Definitely wrought, a single spike split into three, each of which was then bent away from the central axis to form a bloom of spikes. A flower with a point to it, a definite attitude. An attitude which translates to, in effect, Butt out. Buzz off. Go away. NOW.
Some are not wrought. These, if metal, are sharpened bolts, or nails, set blunt end down, and pointy end up, protruding through a board or strap of iron. In case you don't get the idea by simply looking, and do in fact try to sit on them, or lean on them, or simply rebalance your balance following a slightly unsteady moment in the midst of an over-reaction to a clod of malingering dog-brown, then they bite, and bite quite well.
And the others, the not-metal? Well, anything sharp does it. Broken glass is more often used to top walls, but works along external windowsills, as you might imagine, and more decidedly catches your attention because everyone, at one time or another, has had an encounter with broken glass, and knows, sincerely knows, what broken glass does to flesh.
So that works too.
And as a result, you take your butt and park it elsewhere, along with the rest of your self, and leave those window ledges to their own thoughts, all alone, and butt-free.