use it whenever you feel like it. or whenever it sounds good. no really strictdefinition. can be used pretty much anytime, but mostly when happy or saying yes. opposite of blahmafragulus.
person1: are you coming to the thriceconcert?
person2: you know it.
person1: kijizzle! see you there.
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.
We have a Zoom meeting in a few minutes and I’ll probably go pajama casual.