Nu-fun is where you think you're having fun but you're not. Typically used when your vocabulary wouldn't otherwise qualify you to share your opinions on the Internet.
Person 1: Dude, Breath of the Wild was prettyfun Person 2: Don't you mean nu-fun?
Pajama casual is a term used when working from home and preparing for a video conference. All business above the waist and your pajama pants down below.