What do you think about me going out with just a dress and no underwear when it's hot outside like the last few days here?
Why do you not wear underwear when it's hot?
I just find it more comfortable.
There's nothing wrong with not wearing underwear with a dress. Your clothing and undergarments are your business and no one else's.
Told everyone at work that I don't wear undies and how hot it is, such a nice day.
You really shouldn't go around telling everyone that you're not wearing "undies" as you put it. No one needs to know the type of clothes that you're wearing or not wearing.