Mistress loves the idea of my panties coming undone during the day, having them slowly make their way down my legs and out my pants exposing my fetish to all.
A large wet spot on my pants suggests i love it too. I tied a very loose knot and waited throughout the day for it to happen. They became so loose i had to check several times to see if they were there.
Eventually they came undone, as i did with them.