We have a smaller sleeping bag that we use as a temporary hide/container for our retics when we need to do a full enclosure cleaning. They figured out pretty quickly that they really like it in there.
When I had a large BCI & wanted to clean her home, she loved going into the soft-sided "small dog carrier" that I have- I put a thick towel in it & it made a very cozy 'cave' with built-in ventilation. Much like your sleeping bag...
Rudeness is the weak man's imitation of strength. Eric Hoffer(1902 - 1983)
“The greatness of a nation and its moral progress can be judged by the way its animals are treated.” ~ Gandhi