Ive been a 36G since secondary school and over the years Ive found several things in there (aside from my boobies! 
)I often find bits of food, sawdust (I have a hamster!) and staples (I have really no idea how they find themselves in there!)
You find sawdust and staples in your undergarments. Hmm. I suspect you’ve torn a seam and are leaking your stuffing.
Do you find bran and pins in your hat?
Many bats are really tiny. Think thumb-sized bodies. But yeah, bodacious knockers and “a few drinks” the night before and she might not have noticed for a while. I’m surprised the bat didn’t kick up more of a fuss earlier though. Maybe too surprised to have that mass of flesh landing on his head.
But, just read it in a slow… seductive voice. Preferably somewhat deep (inspiration.)
Then go write the full length erotic novel featuring you will instantly think up.