Where did that battery go?!

Apparently, there is a ghost in the tiny bitty room I rent. On Saturday night, I was passing some photos from my camera, which required me to take the battery out of the camera to get to the memory card. I was all bundled up in bed (because it was freezing!), and placed the battery somewhere in the comforter. Later, I had to get out of bed to grab something, and I heard the battery go down between the bed and the wall. The bed is in one corner of the room touching two walls. I thought: "No big deal, I'll retrieve it in the morning." Besides, who wants to move the mattresses and make noise at 9pm?

Camera and battery are this exact same model

So I let it go. The next day, I went under the bed looking for it. Odd; I couldn't find it. I looked a bit harder, then harder, then a lot harder. I stripped the bed, I took the mattress and leaned it against the opposite wall, same with the box spring. I took the whole bed frame apart (it's a simple wooden skeleton type). I couldn't find the battery. I emptied sealed boxes that were under the bed with my summer clothes. Nothing. I looked inside every shoe under the bed and nothing. Then I put the bed together again and emptied the closet, every single drawer, every single box or container and it wasn't there.

3.5hrs later of ransacking a room that's only 12.5ft x 9ft, I stripped the bed again, took pillows out of pillow cases, undid everything... and put it back together. No battery. I retraced the few steps I may have given between my room, the bathroom and the kitchen area, in the strangest case that maybe it got lugged in my hoodie and made off with me outside my room. Nothing still. Asked the landlords and they haven't seen it either.

So, how do you deal with these ghosts that take your stuff and make them disappear into thin air? Am I supposed to offer a sacrifice in exchange for my camera battery?!