Boob size can come into play too. For women with big boobs, there is more to cover and more to see; so some instinctively cover that up first.

But you're right about the cold thing. When my ex and I were living the nudist life, she would sometimes opt to just put on a T-shirt or tank top - and go bottomless - if she was a little chilly. No reason to cover the rest of her body.
If she was running around the pool or taking part in some physical activity, she would often clutch her big boobs; mostly to avoid the "flopping around effect." She said that after a while it was actually physically painful.

My fiancée is small-tittied. She doesn't have any of the "big boob" issues my ex had. She can go braless or topless and run around all day without feeling any discomfort. And her instinctive reaction to being "caught" nude is to cover her kitty.

I think it is a natural reaction, my has done the same thing. She feels you see more up top with the nipples, and her fur covers the lisps so you can’t see as much unless she was spread. I love it because I would rather see the kitty too.

I pretty much agree with the above, a difference being that some automatically first cover that part which is potentially most embarrassing to them.

For example, my wife when caught nude by surprise by a group she didn't know well immediately covered her tits and kept her arms that way until she could turn away. There was a mixture of contemporaries in the room, male and female, so we all had a discussion about it when my wife returned, clothed.

This was back in the days when almost nobody shaved their bush so the consensus was that except for color all pussies look basically the same initially but there are many immediately obvious differences in tits and many, if not all, women are insecure about their tits so they get covered first.

Hmmm.
 

Here’s 2 for you

She is absolutely stunning. Fantastic tits, thank you for the picture with them uncovered.

These days it's a bit cold out here in the Midwest. So my fiancée has pulled out the old bathrobe...aaargh...

But it's actually not so bad. She came out of the shower this morning with a towel on her bed, her bathrobe on...but totally open. She wears it just to stay warm; not to cover up anything.

It's still a nice look!

Like this?
 

All the time!

First, wrapping up her hair and second, standing in front of the bathroom mirror...

Beautiful
 

She's beautiful. Love the side boob visible in the pic where she's holding the towel. Thanks for sharing.

my wife
 

she sure does! always has and hopefully will continue!

Really nice body. Thankxxx