I own a lovely large cage. It's a dog cage, one that's sized for dogs like great danes and st bernards, so it's very big - about 1.5m x 1m x 1m. You can fit people into it extremely comfortably. At an event I ran, we had three people locked in the cage and then they started wrestling with each other... it was very entertaining to watch, and it gives you an idea of just how roomy it is.
I have always had a thing for cages. It's not necessarily a BDSM thing, either. For example, I like being in cages myself, even though I am exclusively dominant. For me, it is like when you are a child and you play in boxes - it's like having a fort, a place where the rest of the world doesn't matter, somewhere cozy and nice where you can settle down and just relax.
My cage is very comfortable for short term snuggling down and relaxing. I knew it was big enough to make someone sleep it it overnight without harming them, but I wasn't sure if it could be done comfortably.
Enter, the boy.
Last night we were mucking about with the cage, at one point discovering that you can easily fit two people who are snuggling into it. I talked to him about how much I adore cages, how I find them fun and secure when I am in them, and how I find them sexy and exciting when I am putting someone else in them. How I always fantasize about having someone sleep in them overnight.
He made a joke about sleeping in the cage that night. I laughed it off. A little later, he joked about it again. I told him that I doubted it would be very comfortable for him. He told me that he'd be fine.
Long story short, at midnight I was tucking him into the cage with lots of pillows and blankets. I deliberately did not lock it, because I was going to be sleeping in my room (the cage is in my living room) and I wanted him to be able to get up and pee if he needed it, or if it became too uncomfortable, come in and get into bed with me. I was not comfortable with locking him into something if I wasn't going to be able to be in the same room all night.
I covered the cage with blankets to keep the light down, as I was going to be up for a couple more hours in the living room and I didn't want to disturb him too much. This is a trick that you learn if you have caged pets - growing up I had a cockatoo, and to put her "to bed" each night I would cover her cage with a large sheet, to keep the cage dark.
Half an hour after putting him to bed--or perhaps, "to cage"--I heard soft snoring noises. Two hours later, they were still going on, and I went to bed myself.
I got up in the morning and came out into the living room only to find that he was still asleep in the cage. I sat down on the floor by the door and uncovered that part of the cage. His eyes opened.
"Hello," I said softly, smiling at him.
"Hello," he said back, smiling that wonderfully adorable boy-smile.
Then he said, "I told you."
Indeed you did, my boy. Indeed you did.