Oh that part's easy. I left the drawer open by mistake. I'm blind as a bat without my contact lenses, and, wellp, she snuggled down into my drawer behind the underwear and I never saw her. I noticed I left the drawer open, and closed it so I wouldn't bonk myself on the head when I got up in the morning.

Or something like that. Hopefully she wasn't in there for long. I noticed the contents of my sachet were all over the drawer this morning - she must have enjoyed the aromatherapy...