I have a sofa bed that can be used either as a single bed, or as a double bed when I unfold the bed frame. I generally use it as a single bed: it is more convenient and allows me to have more space in my small apartment. In that case, I pile two single mattresses up on the bed frame. When I have a guest, I convert the sofa into a double bed, and I put the two mattresses side by side. Unfortunately, that arrangement really requires to sleep still, which is not very suitable for closeness (I mean by that sexual relations but also simply cuddling). Indeed when there is the slightest movement the outer mattress tends to slip out of the bed frame, which doesn’t have a high edge.
That being said, having someone at my place is rare enough to prevent me from buying a spare double mattress. Is there an easy way to keep the two mattresses together, or at least to prevent the outer mattress to slip out?
Here is the reference for my sofa bed: http://www.ikea.com/fr/fr/catalog/products/00318881/
And my mattresses are those ones: http://www.ikea.com/fr/fr/catalog/products/30272339/