I'm sitting here in a Snuggie, half of me.
Someone gave me one as a gift, completely unexpectedly. So I'm trying it out.
Mine is a little longer than it needs to be and the sleeves are more expansive than they need to be. But I've got them pulled back.
It seems to me that a good old fashioned bathrobe would do the trick about as well, except it wouldn't cover your legs. The whole idea of having the back completely open doesn't appeal to me. I'm not on a couch but on a regular wooden chair.
I normally (in the winter) wear some kind of long john pants under my pants, like a jogging suit, but I didn't do it today. So I've been colder than I like most of the day.
Snuggie. It's all the rage. I wouldn't have bought one. But if someone gives you one, that's how to get one.