I could not tell you everything that's under my bed- well I know what's under my side- containers of stored winter clothes, etc. but my hubby's side has misc. junk that he shoves under when vacuuming as a lazy attempt at cleaning up lol. Not that he has anything weird under there, just saying I don't know exactly what is there.
Playing devil's advocate- but remember the "Craigslist Killer"? I watched the movie the other day and there was something like 16 pairs of women's underwear, as well as a gun all hidden under this guy and his fiancee's mattress and she had no idea. She also had no idea and didn't partake in his deviated sexual fantasies. That's why he sought out others online to help him fulfill these desires. It's like he had two lives- the charming med student engaged to this beautiful girl from a good family, and the murderer who was into sexual torture.
It's possible that BD wasn't aware and didn't partake in these things.