Just found an old stained underwear in my bathroom air vent after not opening for 16+ yrs…

When we first moved into this house in 2008 we had some guys paint the interior, and they painted over the vents so this hasn’t been opened since then. I decided I wanted to clean it today so I opened it and this is the first thing I saw🤮. It’s stiff and stained and I’m afraid to look at what’s inside…disturbing to think that it’s been in there since I was a kid💀