My brother is gross...

I drive a Jaguar x350, which has a gear knob made of wood, well my brother, being the genius that he is, found out you can unscrew this, so he did, and started bragging to me how he unscrewed part of my car.

I told him to screw it back on before he drops it on the ground and scratches, chips or cracks it, instead he engulfs the whole thing in his mouth.

I told him fair and square that he now has to sanitize it.

Oh and the car is used, no clue where that gear knobs been before...

What's a gross thing you've seen someone do to something that you own?